Internet connection keeps dropping on mobile phone devices

[Helen1510]

We have 3 different mobile phones in our household which the internet connection keeps dropping in and out 

we are all using our mobile data to access the internet 

[Paul407]

We have 2 phones on sky mobile and at various locations (home, work, out and about) the internet connection drops even though I have 3 bars and LTE showing. It's happening both phones and is only fixed by a restart. No help from Sky. I'll be cancelling contracts if I can find a way to get hold of them!