HomePod Mini/ 2 thread networks/ devices frequently inavailable

I have 3 Nanoleaf bulbs (matter) and an eve flair (thread only) connected to home assistant. I have 2 Apple TVs (old and not thread border routers) and 1 HomePod mini. These devices are frequently becoming unavailable, it seems that I somehow have 2 thread networks and every few days the HomePod mini changes its network. To solve it I have to reset the HomePod mini and it comes back into my preferred network. Since getting the HomePod mini years ago I have set up a TP link deco mesh wifi operating in access point, with my original ISO network disabled. Is this why? I don’t have any other devices that would operate as a thread border router and cannot figure out why I have the 2 networks. It’s very annoying and would like to get rid of one of these networks. When I look at my ISP IP address page (home hub 3000 through bell aliant) the HomePod mini is still connected to its 5GHz network but 0 bars of service/ doesn’t really seem to be connected and I can’t remove it.