Hue Bulb/Hub "Thing" Dropout

This has probably been covered before I can’t find it.
I have a combination of Hue and Osram bulbs connected to a Hue Hub and then connected using Hue connect. Everything works fine for about 2 weeks and then I lose the ability to control the bulbs from within ST they work fine in Hue app and via Alexa (via hue not ST) so know the issues lies with ST connections. A stab in the dark but anyone know why this occurs? The only I can seem to get it back is to.delete it all from ST and start again.

I’ve tried Hue connect and reconnect smart apps both do the same thing.

I’m in the UK not that it should matter…

Any advice great fully received.
Jamie