Galaxy S6 Active 5.1.1 IMEI NULL – Please help

Hey guys,

I’m new here, so please excuse my tread if it’s already opened or you guys already discussed about it, but I’ve searched everything to find a fix, nothing out there.

I’m having a Galaxy S6 Active and since a couple of days ago, my sim haven’t been recognized. After a few hours of checking and re-cheking the sim, I finally realized that somehow… the IMEI number is missing. When I check, IMEI is NULL.
So now I have Baseband version Unknown, NULL IMEI number and no Mobile Network Connection.

I’m not living in the USA, so I don’t have AT&T.

If anybody can please help me, I would really appreciate it.

I already tried flashing back to stock firmware 5.1.1 via Odin, nothing changed.

Thanks a lot guys.