Network issue with some sides not properly loading

[solala]

I'm having issues with some websites not loading for example twitter doesn't load some pics or steam is having issues showing some websites. When I restart the router it sometimes works for a few hours but then again. I'm having the issues on mobile as well as on PC. However, this seems to be a problem that only appears in my local home network, when I try the same thing in cellular network or in the university wifi it works without any issues. I don't know though if the problem is on my side or whether it's provider side. Any ideas how to fix this? The problem appeared maybe a week and a half ago or so, I didn't change anything in the network settings or such :/

https://gyazo.com/40239b7930a498945e41229d6d5cd18d - twitter desktop
https://gyazo.com/ca9dfd44e285751d7b8e9fc27f0f99f0 - twitter windows app
https://gyazo.com/7db51d0a5fbb59cc8113b54ea9a33ae7 - steam desktop

If you need any more information I'd be happy to provide it as this is really pissing me off right now

 

[Beach]

Those are either ISP or router connection problems, I would suggest contacting your ISP.

 

[solala]

Could this be because of that attack DynDNS received the other day? (not sure if its still going on or not but..)

I'm German so the attack didn't affect me but however the issue first showed up like two weeks ago or so

 

[solala]

Those are either ISP or router connection problems, I would suggest contacting your ISP.

Thanks, a lot of people actually told me to contact my ISP but I wanted to see if any of you guys had other ideas on how to fix this