Any home security people on here - going from monitored to unmonitored

I disconnected Cox yesterday, along with my hone phone. I had also stopped my alarm monitoring at the beginning of this month.
Last night when I set the alarm when I went to bed, it alarms (not house alarm), letting me know there’s no phone signal. I have to re-arm it again. When I turn off the alarm, again I get the alarm that there’s no signal. I have to enter the code again.
It just started this last night when I got rid of the phone system, it hasn’t been monitored in 2+ weeks.
Anyone know how to turn this function off?