Webhooks Could not create SSL/TLS secure channel

edited October 2018 in Photon Chat

I added a webhook to my Photon Chat application using the dashboard. The URL is https and the web server runs a Let's Encrypt certificate. I also use custom authentication and it works great. My base URL for the webhook is the same I used in custom authentication but webhooks for some reason don't work and I get the following message on client:

Chat Operation 0 failed (Code: 32752). Debug Message: Web service error: URL='https://{omitted}/api/v1/ChatWebhook/false' WebExceptionStatus=SecureChannelFailure Reason=The request was aborted: Could not create SSL/TLS secure channel.

Is there anything I can do?