The connection is no longer usable because the server response for a previously executed statement was incorrectly formatted
Based on the details you've provided, it's likely this error is being caused by a network issue between the AX server and the SQL Server.  If you have a network team, it might be good to bring them in to investigate if there are packets being lost between the two servers.
Another possibility is that there is an issue with the driver AX is using to connect to SQL Server (SQL Server Native Client 11.0).  Some possible options there are to

reinstall the driver,
update to the most recent supported version of the driver,
try a different driver, like MSOLEDBSQL (if that's configurable in AX, I don't know anything about that)