I just now found the same thing in my QBO company.  I deliberately updated an existing Vendor bill on September 10, 2022 at 8:52PM.  This vendor bill had already been paid and was last edited on August 1.  On September 10 at 11:57PM, the history of the transaction shows that I edited it again and negated the change I made at 8:52PM as to the account and amount, but the description data field says "Melio amount change".  I DID NOT MAKE THIS CHANGE.  I DO NOT USE MELIO!!!  This is a serious problem that needs immediate resolution.