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I didn't understand most of the article. There are a lot of names that I don't know and don't understand. Plus that, the first link doesn't lead to anything

You can read this article if you have lag http://help.tankionline.com/topics/2361-how-to-reduce-lags/
Read this also to change your password if someone tried to enter your account http://help.tankionline.com/topics/2352-how-to-change-my-password-email-address/

Contact help@tankionline.com They might explain you the problem

It mainly happens because of lag. You can take a screenshot or a video of you not being able to take a gold box and sent it to help@tankionline.com . They will add 1000 crystals to your account

Contact help@tankionline.com . They might fix your problem or give you the reward if you didn't receive it

The Developers in the V-log said that we should not worry about anything and that they are working on it.
I don't know if you can play Tanki on HTML 5. Just be patient until developers release news about this problem

Sometimes happen. All you have to do is press the key where your tank is moving. If it's moving in the front direction then press the up key once and your tank will stop the movement