We are using an old SOAP web service hosted somewhere where I don't have access to. We've been using this service for years, last week out of a sudden we started getting time out exceptions. We were able to reproduce this on all environments.

The web service now just always times out when sending SOAP requests. However, some operations support GET/POST methods and these actually work. So I was able to use GET for one of the operations but not the other since only SOAP requests are accepted for that.

I tested different TLS versions, and they all fail with exceptions except 1.2 which just times out.

I used Postman and SOAPUI to import the wsdl and test the web service and they all just keep loading until timeout.

The only other thing worth mentioning is that we noticed that the SSL certificate expired around the time the timeouts started. It's updated now by the client. I don't know if and how can a new certificate affect SOAP requests only.

Any ideas or ways to debug this is appreciated.

In case it's useful, here's a Wireshark capture of the request: