Made an appt for 11:00am, showed up at 10:55 for check in and was told there would be a wait. NP. 15 minutes later I explained to the Sprint rep that I have some of the worst cell service I have ever experienced and I needed to know if it was the S7 or the Sprint coverage. He tried changing the network setting from automatic to LTE/CDMA, I let him do it then explained I had also played with those settings and found no difference. He then took my S7 to the "tech" desk only to be informed by them that the "tech" desk was down due to a software changeover or upgrade or change of some kind, it was not exactly specified or determined how long it would take for them to be up and running. The rep then decided to attempt a sim card change out. Unfortunately my specific sim card was not in stock. An hour later I left in exactly the same spot that I started in. I would like to make it clear that the rep was great under the circumstances.