Phone [Q] Unlocked sprint htc wont let me search for network pls help

Ok so heres my problem I unlocked my sprint htc one i put a at&t sim card in it will read the sim card but it i don't have any signal
ive put it on wcdma preferred but when i go to to search for a gsn network the search button is clear and wont let me tap on it..

Also ive located my profile settings using my msl so im able to edit them but don't have the slightest clue were to start.. i want to change my sprint provider settings so that my phone will be unlocked completely.. is their any way ??/ please help