Wifi connection issues after opening lid / sleep mode

For quite some time I have the following issue. I usually put my MBP into sleep mode by just closing the lid.

4 out of 10 times I experience problems with the wifi connection after opening the lid again. When I go onto Safari the websites usually don't load at all. Refreshing the websites doesn't seem to work either.

Sometimes it just takes some time (approx. 3 to 5 min) or I need to shut the lid and open it again. Other times only restarting my router seems to work.

The wifi is always connected on my MBP and the router shows an active connection too.

I have spoken to my internet provider and they acknowledge that they have seen the internet connections dropping quite often and are checking the line atm. I've also got a new router but the issue is still persisting.

I just want to check if there is something I can check on my MBP so I can rule out an issues between my MBP and the router and focus on solving the issue with my internet provider?

Many Thanks in advance