When I'm in my server and I /rename Disasters then /stop and I /join Disasters and don't work! it said still same name on my server not Disasters! D:

Hello!, please make sure your server is OFFLINE first, and then /rename (name) in lobby, Thank you.

<span style="color:#f1c40f"><span style="font-size:26px"><strong><em>#1 XRun Player</em></strong></span></span><br /> <em>1st Place on 7 out of 12 maps.</em><br /> Beat MyNameIs12345 on Sand by 0.001 seconds (skrub).

Thank you @DarkyMinecraft, I'm so happy now! :D