Using Hub 3 (VM) and getting error messages on SKY Q saying there is no internet connection.

Hi,

Long time user of VM Hub 3 which has never been a problem.  We use 2 mobiles, laptop and SKY Q and have had no issues over the years until recently which concerns me. The hub is at the front of the house in a different room but this has never been an issue.  Both mobiles show as having 3 to 4 bars generally and the laptop is always full WIFI connection. 

Now my O/H tells me that he gets an error message on SKY Q that there is 'no internet connection'.  I will always go check my hub and it is lit up as usual.  We can still use most functions of SKY but some of his saved recordings have disappeared suddenly and also those that remain have an empty front picture of the film/show or the frame can take a long time to load (although selecting the empty frame does still allow us to watch it).  We are having to select programs by avoiding using the SKY Home button completely or the error message pops up. 

I have turned off the hub which has made no difference.  He has unplugged SKY with no success.  We also  reconnected to my VM via SKY settings but the problem remains.  

Any thoughts much appreciated as am at a loss what has happened and whether the issue is with SKY or VM.  

Thank you