It is just a flood protection from the Master Server. Don't be so quick to keep clicking things, and you wont get the message, simple
.
If you are trying to join a full server and get in ASAP, just wait till you see a free slot, and not keep clicking away hoping you'll get in.
NOT A BUG.
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If you are trying to join a full server and get in ASAP, just wait till you see a free slot, and not keep clicking away hoping you'll get in.
NOT A BUG.