When I connect my 2TB Time Capsule to my MacBook Pro via Ethernet, I can't load any webpages even though I am connected to a network that works on my other devices

Good morning Apple Support community,

I have recently purchased a Thunderbolt to Ethernet adapter from Apple, to connect my 2TB Time Capsule (Model A1409) without having to host a network. When I connect it to my MacBook Pro (Mid-2012, Retina, Model A1398, OS X 10.10), I am still connected to my home network which usually has internet access, except when it is connected I lose any internet access and webpages won't load in Safari. The Time Machine backups complete just fine, however I want to be able to stay online and backup at the same time.

I should point out that the Ethernet cable is plugged into one of the three ports on the Time Capsule - it definitely isn't in the WAN port.

Can somebody please advise me on what to do to be able to complete my backups AND have internet access at the same time? Where am I going wrong?

Regards,

Matthew