For the error that you are getting, do you have multiple client SSL on your VS and one of the profile is acting as default SSL? Please refer below articles.
The above solution did not do the trick even I removed the chain, most likely because I am using the same key/certificate just using a different SSL profile to do the test.
I tried using a different key/certificate but also different domain and it worked. On December 2nd week, I’ll get the new/replacement cert and will test the procedure in the KB and see if it works on same domain name different key/cert.
If you are running a script to swap the clientssl profile of VIP, the below will work (you might need to have a standard where all clientssl profiles actually start with with word clientssl though)