While Pokemon GO is extremely addictive, it does have its share of problems, even server issues notwithstanding.
When the game is up and running, you might encounter some hiccups, and here are the most well-known problems and bugs.
Location Is Unavailable
Even when the game is stable you might run into this every now and then. The game will be patched at some point to improve this, but there are a few things you can do on your side of the equation. Go to your location settings and make sure you select the "High Accuracy" option. Typically it is selected by default, but if it is not you might encounter more issues than normal.
Also, a thing of note is when leaving a heftier Wi-Fi signal and going to a mobile network signal, you might need to turn the Wi-Fi option on and then off for a second time for the game to recognize that you're no longer on Wi-Fi. That, or you could always just quit the game and restart.
Trainer Progress Temporarily Resets To Level 1
This one would cause panic in just about any would be trainer, but Niantic believes it to just be user error. When you first boot up the game you'll have two login options, and occasionally you might accidentally choose the wrong one since they're so close together. If you notice you're back at level one, just log out and then relogin as normal and things should be back to normal.
You Already Own This Item Error (Android)
Occasionally the game freezes for no real reason, and if this happens while you're purchasing PokeCoins, you might get this message. If you restart your mobile device and things should update once you log back in.
This Item Is Not Available In Your Country Error
This happens when you go to download the app for the first time. If you see this message, it typically means your Google Wallet might have a different country selected. If that doesn't help, though, make sure to reach out to Google Play support.
PokeCoins & Purchased Items Don't Show Up In My Account0comments
If you bought something and it isn't showing up, you'll want to sign out of the app (don't' just close it). Once signed back in the items should show up. If they don't, you will need to restart your mobile device.
If you come across any other prevalent issues, let us know in the comments!