UPDATE 2024-01-09: Cause turned out to be hosting provider was not allowing access to port 6379. Below is comment from Tobias:
So it turns out that my hosting provider is not providing access to port 6379. That is why it kept failing. Thank you all for your comments and help.
Hi Tobias,
Please enable public network access if you haven't already. You do this on Private endpoint blade, as shown below:
Once above is done (give it a minute to take effect), any IP is allowed by default, unless you create a rule on Firewall blade. For testing you might want to delete any firewall rules, click Save, wait 1 minute, and verify it works. Once it is working, create a firewall rule for your web server public IP and test again to make sure it still works.
Please click Accept Answer and upvote if the above was helpful. If you still need assistance add a comment below with your pricing tier, network option you selected during creation (public, private endpoint, vnet), and other networking details if relevant.
Thanks.
-TP