Xfinity sos

I have been trying to figure this out for almost 2 whole weeks. My xfinity app only has 2 tabs, overview and account. I tried it all even went to the store and no help. What's worse is that no devices are connecting properly and I work from home along with family coming to spend the night Saturday. A few days ago I went to the store and got a new modem and plug that ended up not working. Then today I had a tech guy and install it and he didn't know either. I'm in crisis mode