If you can’t play Youtube video your iPhone, and encounter error “Playback error Tap to retry”, you can use methods here to fix the problem. After that, you should watch the video again.
There are 5 solutions you can try. You may not have to try them all; just work your way down the list until you find the one that works.
If you have signed in to Youtube with your google account, sign off then try using Youtube again. It works if the problem was caused by a problematic google account.
Try resetting the router and it may work like a charm for you.
If there is something wrong with the Youtube app, the problem would occur. So to fix the problem, you can try uninstalling it then reinstalling it.
Many iPhone users reported that updating the router firmware work for them. So this method is worth a try. Regarding how to update the router firmware, you need to check the modem model then you can find the detailed instructions on the router vendor’s website.
Follow steps below:
1. Tap on Settings.
2. Tap on Wi-Fi. (Ensure your iPhone has access to your Wi-Fi network.)
3. Tap on the info icon as shown in below screenshot.
4. Change the DNS to 188.8.131.52.
Hope methods here help you solve the youtube video not playing issue.