First of all, check that you have a public IP address on the router. Some ISPs are putting your Internet connection behind CGNAT. This is not popular, but is appearing more frequently nowadays.
Open a browser and go to duckduckgo.com, search for “my ip address”. Does the IP address reported by your browser match that displayed on your router’s Status page (Internet section on the upper left corner)?
If yes, please try these steps:
Disable Access Control at router level. Check PS4 NAT type. Is it Type-3?
Enable UPnP for router. Check PS4 NAT type.
If the above result is Type 2, then enable Access Control and check NAT type again.
If the NAT type in step 2 above is still Type 3, let us know. We’ll see what else can be done.