Can't access xFi app

[BeckyP512]

I recently switched to Comcast Xfinity. The tech who installed the box outside set up the internet for me. The next morning I had to call customer support because I couldn't get on the internet (bad password). The lady I spoke to was very nice and helpful and told me about the xFi app. I downloaded it and I get this message: This site can’t be reachedxerxes-sub.xerxessecure.com refused to connect.
Try:
Checking the connection.
I uninstalled and reinstalled it several times. It's hard to get through to customer service.

While ago we had a power outage and when it came back on I tried the app and was able to sign in. It asked if I wanted to set up a gateway, which confused me. I thought it was already set up, since I've been using it over a week. Then it said there was a technician working in the area.
Anyway, before I had a chance to do anything we had another power outage and now that power has been restored I'm back to the same error: This site can’t be reachedxerxes-sub.xerxessecure.com refused to connect.
Try: Checking the connection.
Please help. I was told to uninstall and reinstall, which I did again, but it's still not working.

[ComcastJosh]

Hello and I am sorry to hear about the trouble you have been experiencing trying to get the xFi app set up. I would love to be able to assist you and help you get it working.  Please click on my name and send me a personal message with your full name and your Comcast account number. 

[Marrie14]

Yes me as well. Except I reset my router using 10.0.0.1. got the x fi app. Forgot all devices and brought them back in to verify Mac address. Then this morning x fi app after type in password says xerexes.sub.xerxessecure.com. Then quickly redirects as Xfinity. Google Xerxes and x finity app.
I think it's a compromised app.
I've had issues for months in requards to divices and internet security. ive mentioned this app. I've mentioned I'm finding I've been redirected to an Xfinity unsecure network without my permission. My network will show as I've made SSID and so forth. Upone doing a network scan it will say unknown SSID 00.00.00.00.00.00 constantly. They've replace my router twice. Now I'm showing no data usage from the start of my bill cycle to the date I called 4/14/20. I used like 600gb on average. Month before only 64gb then prior month almost a terabite!
It's clear my network is being rerouted as I showed no data use I stream three chrome books and a firestick (not jailbroken). I clearly use data.
My home phone... When it rings u see who's called on caller ID. Pick it up I hear nothing. Call the person back they say it rings and then goes dead but doesn't disconnect. Every inbound call does this. Out bound calls out but very static connection. Sometimes I have to hang up and recall. I've mentioned this to the tech and "just make sure all your wires are tight". Everything looks good on the Comcast end with exception now they see no data. I've clearly been compromised and no amount of resetting my router has fixed it.
I really am concerned about my network security