I have not experienced problems with the Firefox browser or the Chrome browser for iPhone and I have an older iPhone, iPhone 6s Plus. I was able to get the iPhone Safari browser to work by doing the following.
If you’re using an unstable or inefficient network connection, then this may lead to websites not loading properly Safari. You need to make sure that your internet connection is functioning properly with an appropriate network speed. If you’re on cellular data, I’d suggest you switch to Wi-Fi connection as it is much more reliable. If you still face the same problem, then you may try to modify your DNS server settings on your iPhone. To do so, follow the steps below.
- Go to ‘Settings’ and select ‘Wi-Fi’.
- Tap the ‘i’ button in front of your Wi-Fi network connection.
- Press the ‘Configure DNS’ option and select ‘Manual’.
- Select ‘Add Server’ and add the Google DNS servers 18.104.22.168 and 22.214.171.124.
- Remove all other DNS Servers
- Select ‘Save’ to finalize the changes.
- Turn iphone off and back on
If that doesn’t work and you are on IOS 14.2 check the following link for solutions.