Reverse Transactions

You may reverse transactions D365 easily with one button. 

Some can be reversed from voucher transactions directly. If have subledger, some can be reversed from the modules.

But some can not be reversed but have other options from reversals like to create credit notes. 

You may find the link below with details.

https://learn.microsoft.com/en-us/dynamics365/finance/general-ledger/cant-reverse-transctns