Ssl/tls not working when site accessed from old android

I have automatic Netlify TLS certificates enabled via Let’s Encrypt. I can access the site over https from both chrome and safari on both my 2019 MacBook Pro and my iPhone 11. Others have been able to access on their phones (iPhones and Google Pixels).

However, I ordered an old Samsung Galaxy J1 off of eBay so I could test functionality with it. When I try to access the website, I get “Your connection to this site is not private.” I am able to access other sites. And I tried following the steps in this guide (except for disabling antivirus), and it didn’t help.

My site name is

You’re likely affected by: