Hi @FluxGT
If @JimM1 's suggestions don't help then you may have to look for other options.
A single router often fails to reach every room in a property, even relatively small ones. From what I've read on this forum, the Sky Max router has poor wi-fi range, but that me be subjective. Other than Sky Boosters/Pods, you could try:-
1. Invest in further hardware and create your own wifi Mesh with sufficient devices to cover the whole house. There are multiple suppliers you can pick from that all work well, but this can be relatively costly (however once invested, a Mesh system would work with any broadband supplier if you eventually move away from Sky).
2. Homeplugs/Powerline devices can provide a hardwired solution from your Sky Broadband router to other rooms using your mains wiring, you simply need a power socket near the router and another in the "target" room that then allows devices to be hardwired (or connection of a wifi hotspot in the target room).
Personally I went with option 1 as some rooms in our bungalow were just too far away from the router to pick up a wifi signal reliably. This also made wifi available on our patio which is a bonus when the weather is good.
There are plenty of very knowledgeable people on here that can offer advice / help in much more detail if you need further help.
