Some fund houses don't allow modifications in the SIP. In this case, you can initiate a new SIP with the amount you'd like to invest. In case your fund house has provisions to top-up your SIP, then you can do so by logging in to your investment account held with the fund house. If you want to automate increasing your SIP amount, then you may consider investing via step-up SIPs. These SIPs automatically increase your SIP amount at regular intervals, and you only have to maintain sufficient balance on the predetermined dates to facilitate smooth investment.