Well, you didn't have to change your screen name.!
Its probably cause' your phone has a virus or bug.
Ill show you how to reebot:
First you: Hold 'R' don't let go of it
Next you take out the battery for 30 seconds but keep on holding 'R'
When 30 seconds is over put the battery back in (never let go of 'R')
Keep holding 'R' until it resets 2 times!
It should stop it.. if it doesn't then call custormer servicee ! if it does then put the big green plus sign (Me being helpful
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my sidekick slide was having a resetting problem where it would say your device needs to reset it will restart automatically, so I tried all kinds of rebooting and stuff and nothing worked, this started after I went to around .60 cents on my prepaid account and it said I needed to buy a card and put more on my balance then sign in when I do so, so I bought it that day and signed in and about 3 hours later it started doing this resetting and it deletes all my things. So my friend thought maybe changing the username would work since the other username used to be on a monthly plan. so I called customer service and changed the username and after that it seemed to work, well it worked for 2 or 3 days now it is doing the resetting again, please help me thank you.!