No serial number for Galaxy S5 SM-G900R7

[AC Question]

Okay so bear with me. I purchased an unlocked galaxy s5 from a private seller that came with the box and etc, was on Ntelos network, the serial number is nowhere to be found in the phone settings, behind the battery, or on the box. The phone has meid numbers such as pesn, dec, and hex. I tried several apps such as phone info which listed a bunch of 0's, eleven to be exact as the s/n. The phone is indeed genuine according to the genuine galaxy app. I contacted samsung help report through chat but they were of no help and told me to call them, which I can't since the phone doesn't work with my straight talk at the moment. I had received a straight talk sim to use from At&t but they assumed it was bad and will be sending me another one. The odd thing is I had a verizon phone with straight talk sim and it worked in the phone, just didn't have data. I would like to know if anyone knows a way to find the original s/n. Please don't tell me to check the phone status and etc., i already know how to do that, it isn't there. Thanks