Hello @Yash Paranjpay,
welcome to this moderated Azure community forum.
Last year, Microsoft finally replaced it's TLS certificate for encrypting the traffic with the IoT Hub.
Check out this blog post with more background information.
Because you are using an ESP, you are probably still pinning the old Baltimore certificate.
Can you check it the old Baltimore certificate is being used?
If so, replacing it with the new Digicert one is a simple solution. Check the link above for more information.
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