WHAT "CAN NOT UNDO RESTRICTION" & "NOT ALLOWED" MEANS When you have seen the message (Can Not Undo Restriction) or (Not Allowed), it means one of the following: 1.) You entered 5 or more wrong codes into your phone. Some models only allow 3 chances. 2.) The phone was bought off Ebay and the seller did the same as above. This may be why they sold it. 3.) You have browsed around looking at other peoples phones and assumed the code that worked for their model, would also work on yours. All IMEI numbers are different, which means every code for different phones will be different. 4.) You kept entering the same code over and over when seeing "code error" the first time. You should only enter a code ONCE!! YOU ONLY GET 3 TO 5 CHANCES TO ENTER THE CORRECT CODE