If you are experiencing any of the issues from the article's title you may want to clear the in-game cache. Below is how it can be done.

Before clearing the cache ensure that your Panzerdog ID is linked to your account. 

Go to the game menu:
Click/Tap «Settings»,  
Click/Tap «Developer»,
Click/Tap «Clear cache».

Please contact our support team in case that does not help.