2.4 GHz signal disappears

I have a number of devices that require the 2.4 GHz signal. Lately at least once per week the Xfinity XB7 router stops broadcasting the 2.4 GHz network. This is true whether I split the bands or use band sharing. Restarting the gateway does not fix the issue. Typically, the 2.4 GHz signal is down for 1-2 days and then randomly comes back. I had the same issue a year ago and swapped out the gateway. That cleared things up for a few months but then the issue returned. There are a number of posts over the past few years in this forum and on Reddit related to this same issue. Not sure why Xfinity has not fixed this.