How long has your certificate been renewed?
You may need to wait 48 hours to identify the certificate or check the certificate details on the SBC and make sure they are correct.
If the TLS connection is closed right away and SIP options are not received from the SBC, or if 200 OK is not received from the SBC, then the problem might be with the TLS version. The TLS version configured on the SBC should be 1.2 or higher.
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