Data on all servers is saved every 3 hours every day, namely:
at 00:00, 03:00, 06:00, 09:00, 12:00, 15:00, 18:00, 21:00 server time.
At that time you may see a notice plate "Saving" and for some period of time (up to 1 minute) the game possibilities can be blocked.

Very rarely the notice can appear between data saving times.

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