Product: Checking or savings account

I held a checking and Savings account at Citibank and on XX/XX/2020 I asked a representative to close the Savings account and to change the regular checking account onto a Basic checking account. 
I also that day sent a first ACH from Citibank to XXXX XXXX that went through. 
I have been trying since then to have access to the rest of my money held in my Citibank account ( {$5100.00} ) first by transferring {$5100.00} and because this did not go through {$5000.00} to myself as was an ACH transfer from Citibank to XXXX XXXX. It appeared to go through but I have not as of XX/XX/XXXX received the money yet. 
Transfer was scheduled XX/XX/XXXX to be delivered XX/XX/XXXX Below are the lists of emails received XXXX is to notify you that the Inter Institution Transfer request ( s ) below has been canceled due to an over limit condition. 
The amount was then changed from {$5100.00} to the permissible {$5000.00} and the transaction appeared to go through. 
Email on XX/XX/XXXX : XXXXThe funds have been deducted from the account from which you requested the funds be transferred. However, the funds may take another day to reach the destination account. 
The request will continue to show on your Activity page as " Pending ''. We will update you as soon as the transaction is complete. 
Then later on XX/XX/2020 : Unfortunately, the account provider has indicated problems with processing your request. 
As a security precaution, until this problem is resolved, we have put a hold on your ability to submit more of these transactions. 
XXXX XX/XX/XXXX : Unfortunately, the request could not be completed, as one of your account providers has rejected the transaction. As a security precaution, we have temporarily suspended your access to the service. Please contact us at XXXX so that we can resolve the problem and restore your access to the service. 
I called this number and talked to a number of representatives over a few days The representatives names were XXXX, XXXX, XXXX, XXXX, XXXX, XXXX and XXXX XXXX learned from a customer representative that my account was suspended and from another customer representative that the account was closed - that a check had been sent in the mail XX/XX/XXXX and should be received in 5 to 7 business days ; that would have been then XX/XX/XXXX if the check was mailed as asserted on XX/XX/XXXX. 
I have learned finally through customer representative XXXX that the wrong account had been closed on XX/XX/XXXX or XXXX ; instead of closing the regular checking and changing to a basic checking account and closing the savings account they closed the checking account. Citi representative XXXX mentioned that they had no record of who closed the account that they did not know who sent the check as they appeared to have no record of it but that they would enquire about it. 
I have as of XX/XX/XXXX not be informed of what happened or where the money is. What is now appearing in the Savings account ( that should have been closed ) is XXXX cents. 
The purpose of a bank is to have customers ' money accessible when needed. 
I have not received the money. 
A bank statement received XX/XX/2020 shows for XX/XX/XXXX other withdrawal for the sum of {$5100.00}. Where has the sum of {$5100.00} been sent, how and by whom is unclear as per the statement or conversation with customer support. The statement furthers shows a balance of {$0.00} in the checking account that was closed without my authorization or knowledge and a balance of {$0.00} in the Savings account that should have been closed on XX/XX/2020. 

The emails sent to Citibank at the address they provided have been all repeatedly not delivered with the message the recipient server did not accept our requests to connect