Connection timeouts

Hi everyone,

I am having issues connecting to several apple services when using my CG-NATed internetconnection. (Other IPs from the same ISP work fine).

For example, I cannot order anything through apple.com or check my orders, as the connection to secure7.store.apple.com or secure5.store.apple.com times out.

I also cannot open Settings>Apple ID>Subscriptions on my iPhone:

Last but not least: apple-music on my Apple TV also does not work:

Neither my ISP nor apple support could help me. Is there a way to figure out if my IP got blacklisted?

Thanks in advance!

Fabian