This is more likely to be a home hub issue where its run out of internal memory.
Try the usual fixes for the home hub, in this order.
factory reset the home hub.
Then turn Smart Setup off.
The links take you to a couple of BT help pages, simply follow the instruction there.
It will restore the home hub to its default settings, so if you have changed the wireless name or password from the default, then you will need to change it back to your own preference.
Hopefully it will allow you camera and app to connect.
Don't think I have ever changed any password on it. Not that competent. Only password I know of is the one on the little plastic tag on the back of the router.
Then it will be the same as that which is shown on the tag, so all wireless devices should simply reconnect.
Disabling smart setup is important, as smart setup can prevent some devices from working.
It would best to do that from a laptop, as it will be easier to access the home hub web interface, as it may be awkward to do on a tablet screen.