These are my updated sequence diagrams for my new module design
Now I have to work with the actual java code design according to the above.
I need to start design the each and every file or class with all the necessary functions with the exact parameters and all even with some sample business logic
SO the person who is developing should just write the code smoothly

Bill Creation:
sequenceDiagram
   participant EventManager
   participant ReferralBonusSubscriber
   participant ReferralBonusService
   participant ReferralMasterService
   participant ConfigurationService
   participant ReferralBonusWorkflowManager
   participant AuditService


   %% Event Raised
   EventManager->>EventManager: _raiseEvent(EventType eventType)
   EventManager->>ReferralBonusSubscriber: handleEvent(serviceSession, event)


   %% Handle Event
   ReferralBonusSubscriber->>ReferralBonusSubscriber: handleEvent(event)
   ReferralBonusSubscriber->>ConfigurationService: isReferralBonusOpted(entityId)
   ConfigurationService-->>ReferralBonusSubscriber: isOpted
   ReferralBonusSubscriber->>ReferralMasterService: getReferralDetails(bill.getReferralId())
   ReferralMasterService-->>ReferralBonusSubscriber: referral
   ReferralBonusSubscriber->>ReferralBonusSubscriber: buildBillWithReferralDetails(bill, referral)
   ReferralBonusSubscriber->>ReferralBonusService: processReferralBonus(bill)


   %% Process Referral Bonus
   loop charges in bill
       ReferralBonusService->>ReferralBonusService: calculateChargeBonus(charge)
       ReferralBonusService-->>ReferralBonusService: bonusAmount
       alt bonusAmount > 0
           ReferralBonusService->>ReferralBonusService: createBonus(referral.getId(), bill.getId(), bonusAmount)
       end
   end
   ReferralBonusService->>ReferralBonusService: createReferralBonusRequest(bill)
   ReferralBonusService->>ReferralBonusWorkflowManager: handleReferralBonusRequestCreation(referralBonusRequest)
   ReferralBonusWorkflowManager->>ConfigurationService: getApprovalPolicy(referral.getEntityId())
   ConfigurationService-->>ReferralBonusWorkflowManager: approvalPolicy
   ReferralBonusWorkflowManager->>AuditService: audit("Referral bonus request created")
   ReferralBonusWorkflowManager->>TaskService: createWorklistTask(referralBonusRequest, approvalPolicy)

Approval:
sequenceDiagram
   participant TaskService
   participant ReferralBonusWorkflowManager
   participant ReferralBonusService
   participant ConfigurationService
   participant AuditService


   %% Approval/Rejection Process
   TaskService->>ReferralBonusWorkflowManager: handleWorklistTaskAction(requestId, actionCode)
   alt actionCode == "APPROVE"
       ReferralBonusWorkflowManager->>ReferralBonusService: approveReferralBonusRequest(requestId)
       ReferralBonusService->>ReferralBonusService: findReferralRequestById(requestId)
       ReferralBonusService-->>ReferralBonusService: referralBonusRequest


       alt referralBonusRequest exists
           loop bonuses in referralBonusRequest
               alt approval policy is CHILD_LEVEL
                   ReferralBonusService->>ReferralBonusService: updateBonusStatus(bonusId, "CONFIRMED_CHILD_APPROVAL")
               else approval policy is CORPORATE_LEVEL
                   ReferralBonusService->>ReferralBonusService: updateBonusStatus(bonusId, "CONFIRMED_CORPORATE_APPROVAL")
               else approval policy is BOTH
                   ReferralBonusService->>ReferralBonusService: updateBonusStatus(bonusId, "CONFIRMED_CORPORATE_APPROVAL")
               end
           end
           ReferralBonusService->>AuditService: audit("Referral bonus request status updated")

           ReferralBonusWorkflowManager->>ConfigurationService: isCorporateApprovalRequired(requestId)
           ConfigurationService-->>ReferralBonusWorkflowManager: required


           alt required
               ReferralBonusWorkflowManager->>TaskService: createWorklistTask(requestId, "REFERRAL_PENDING_CORPORATE")
               ReferralBonusWorkflowManager->>ReferralBonusService: updateReferralRequestStatus(requestId, "REFERRAL_PENDING_CORPORATE")
           else
               ReferralBonusWorkflowManager->>ReferralBonusService: updateReferralRequestStatus(requestId, "APPROVED")
           end
           ReferralBonusService->>AuditService: audit("Referral bonus request status updated")


           ReferralBonusWorkflowManager->>AuditService: audit("Referral bonus request approved")
       else
           ReferralBonusService-->>TaskService: return
       end
   else actionCode == "REJECT"
       ReferralBonusWorkflowManager->>ReferralBonusService: rejectReferralBonusRequest(requestId)
       ReferralBonusService->>AuditService: audit("Referral bonus request rejection started")
       ReferralBonusService->>ReferralBonusService: updateReferralRequestStatus(requestId, "REFERRAL_REJECTED")
       ReferralBonusService->>AuditService: audit("Referral bonus request rejected")
   end


Bill Cancellation:
sequenceDiagram
   participant EventManager
   participant ReferralBonusSubscriber
   participant ReferralBonusService
   participant ConfigurationService
   participant ReferralMasterService
   participant ReferralBonusWorkflowManager
   participant AuditService


   %% Event Raised
   EventManager->>EventManager: _raiseEvent(EventType.BILL_CANCELLED)
   EventManager->>ReferralBonusSubscriber: handleEvent(serviceSession, event)


   %% Handle Event
   ReferralBonusSubscriber->>ReferralBonusSubscriber: handleEvent(event)
   ReferralBonusSubscriber->>ConfigurationService: isReferralBonusOpted(entityId)
   ConfigurationService-->>ReferralBonusSubscriber: isOpted
   ReferralBonusSubscriber->>ReferralMasterService: getReferralDetails(bill.getReferralId())
   ReferralMasterService-->>ReferralBonusSubscriber: referral
   ReferralBonusSubscriber->>ReferralBonusSubscriber: buildBillWithReferralDetails(bill, referral, isOpted)
   ReferralBonusSubscriber->>ReferralBonusService: processReferralBonusCancellation(bill)


   %% Process Referral Bonus Cancellation
   ReferralBonusService->>ReferralBonusService: findReferralBonusRequest(bill.getId())
   alt Referral bonus request exists
       alt Referral bonus request is pending approval
           ReferralBonusService->>ReferralBonusService: cancelReferralBonusRequest()
           ReferralBonusService->>AuditService: audit("Referral bonus request cancelled")
       else Referral bonus payment has been paid
           ReferralBonusService->>ReferralBonusService: createNegativeReferralBonus()
           ReferralBonusService->>AuditService: audit("Negative referral bonus created")
       else Referral bonus is not paid
           ReferralBonusService->>ReferralBonusService: cancelReferralBonusRequest()
           ReferralBonusService->>AuditService: audit("Referral bonus request cancelled")
       end
   else
       ReferralBonusService-->>ReferralBonusService: No action needed
   end