I have set up the deco m4 as an access point behind the router of my provider. I have successfully connected several laptops, phones and tablets. However, when I try to connect my laptop from work to wifi it will connect to the tp link network but I have no access to the internet. All other devices do not have this problem.

When I connect the laptop directly to the router it does have internet access. Also, when I connect to my old network it does not have this issue. 

What could be the cause / solution to this?

Edit: connecting with my laptop to the booster also grants me internet access, but when I disconnect the cable the laptop remains in the network but has no internet access.