NGINX Self-Signed SSL Blocked By Safari/Apple?

I setup a reverse proxy in NGINX to serve up my mean stack on Ubuntu 20.04 LTS. Everything worked fine, until I added a self-signed SSL cert. After that, I can't access my site on Safari or Chrome in Apple devices; the error reads: "Safari cannot open the page because it could not establish a secure connection to the server". I can access the site just fine in Windows Chrome and Edge browsers. I checked the SSL to make sure it was valid and I tried Googling it and couldn't find a definitive solution that works, but I think there is either a bug in IOS 15.4.1 or they don't allow self-signed SSLs. Anyone run into this before? Any work arounds?
Any help much appreciated.