Not registered on network/insert sim error PLZ HELP

I will try to keep it short. Phone is not rooted and worked on straight talk for one week then started the no sim error. I have called verizon and straight talk even samsung multiple times. The phone will acknowledge a sprint or t-mobile sim but that's it. I have very little access as you know they are greed out. I am new to all this but have worked for over a month trying to fix this. I have went thru several sim cards and I know the hardware is good. I really appreciate any help as my back up is a J100 and I hate it.

PS imei is fine but samsung serial number is listed as all zeros?