IOS app bug

That's odd, Eagle. Mine has been working fine on the app. I would use the regular browser to fix this short term but it if stays an issue, submit a ticket for a bug so that you get a knowledgeable response. I assume that you tried adjusting the zoom on your device.
I have tried a few items. Another odd item, I discovered, it’s only happening on the one Game. I’ve started a few others and they are good.
Might be an outlier. I’ll wrap that one game up on the desktop site.

That's even more weird then. But it's good that it is not continuing in the other games. I hope it stays that way for you!
Items I’ve completed to troubleshoot
Fully updating the app
Changing my phones zoom setting
Uninstalled and reinstalled
Has anyone else seen this issue

Yes, I like to go to the browser web page on my mobile if the chess.com app is not working for me. It is really best for games; for other things I just use browser and I can get done what I need.
I had this issue and resolved it on the iPhone by going into settings/display settings and scrolling down to ‘view’. Changed the setting from zoomed to standard. Make sure you press ‘apply’ and bingo you can see the whole board

I pretty much exclusively use the app but I gotta say I’m kinda sad that it seems like the desktop site has a lot more cool and interesting stuff going on and they clearly focus predominantly on that but I’d wager that a large portion of their user base (and paying customers) are predominantly mobile users.
I noticed a pretty minor bug just now playing a custom position game against the computer where the pawns I had captured were not showing up in the material count. Pretty minor stuff but yeah, I’d love to report the bug and attach the screenshot but it’s not worth it to me to be bothered to log into my account on a desktop computer and send the photo of the bug to myself and all that.