Invalid WS-Security Header when calling service

Have sites set up as 2 separate projects under one account. Both use same core EICannex projects in VisualStudio to make calls and return data. Sites have worked flawlessly for 2+ years. Made simple html + css change and mistakenly republished using FTP method. Now when form submits to grab data, we get

Invalid WS-Security Header
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.ServiceModel.FaultException: Invalid WS-Security Header​

This does not occur localhost, and tests fine, returning data and painting page.

I remember we had this issue when setting account up 2017, and WinHost corrected @ server level config over the phone. No more phone tech support. Something in my FTP publish seems to have wiped this out. They have restored to yesterday backup, but error remains. Both projects were working yesterday, and form post returned correct data.

I did not personally create these projects, and was written by 3rd party, although I have done moderate development for corporate in .NET....

Any assistance as to what/how to get the server configured to get these working again is deeply appreciated...

 

thanks for your helpful response. All questions answered