Pretty self explanatory in settings.

We might be able to help with that info.

Genetically, try clearing the cache on your browser (control key plus shift key plus delete key at same time). If that doesn’t work, make sure your browser is updated.

ios was updated last week. sites were loading properly afterwards.

cleared cache, no effect

I’ve had intermittent issues like that, too. Sometimes I have to turn off my VPN ad blocker, and sometimes the problem fixes itself automagically.

Try installing a different browser on the phone to see if it repeats. You can try Firefox, chrome, edge, or many others. It could be just an incompatibility with an update on the website and where safari doesn’t like it but another browser works.

i am on iphone 7, ios 15.6.1. i believe the issue is not related to my ios.

had rebooted recently

I actually learned that more than fifty years ago at a job that had computers, and it's a lesson I forget over and over.

When in doubt, reboot.