How to deal with -107 Unable to connect with specific username and password

-107 is normally an incorrect SAP username/password.

Please check that the user is active, has not changed password lately, has an SAP license and on the User-screen in SAP is not locked.

Also, this SAP Note on issues if username contain special chars https://launchpad.support.sap.com/#/notes/2297923

Then in the settings in CRMFO clear the SAP credentials and have the user enter the credentials again (should they have changed)

Should this not work then on the server try to do a DTW Test (https://www.youtube.com/watch?v=mlhaqitA26I) to ensure the DI-API work as intended.