cellular/data not working consistently after dropped when on Wi-Fi

I dropped my Icon two stories onto our landing. The back broke off, and it died. I was able to get it working again, but now it acts like it has no cellular and data service sporadically for a few minutes every few minutes before getting service back.

I think the drop knocked the antenna loose, but I'm not sure how to verify or fix that.

Edit-this problem seems to only occur when I'm on Wi-Fi. If I turn off Wi-Fi, it seems to be pretty stable.