Problems with TalkTalk router and network switch

Hi -

I have my router plugged into a netgear power line adaptor which then connects to a TP-link switch (TL-SF1005D).

This all worked fine with my old router (BT's hokehum 4r), but has completely stopped working (i.e. The things plugged into the switch are receiving no internet) since I upgraded to fibre and plugged in the new talktalk router.

Does anyone have any ideas about why this may be happening please?  And any settings I can try changing on the router to fix this?

thanks!

Gareth.