router – Cannot access server from internet

I’m new to networking and I’ve been struggling for a few days with setting up local server, no matter what I do I can’t access it using my public IP. My setup consists of Technicolor TC7200 modem from the ISP + TP-LINK Archer C6 router, which I both have access to.

On my router (Archer C6) side:

• I have setup WAN access using static IP 192.168.0.24
• I made a DHCP reservation for the PC that hosts the server
• I have made a virtual server on port 25501 for TCP/UDP, using the local IP of the PC I’ve reserved.

On my PC side:

• I’ve created a firewall rules (both inbound and outbound) to allow traffic for 25501 for TCP and UDP
• Using dynamic IP for the network, should not need static IP from windows due to DHCP reservation?

On ISP modem side:

• I have opened 25501 for TCP and UDP with the router internal IP (192.168.0.24). Left external IP to 0.0.0.0, but I tried with my public IP as well and nothing changed.
• Alternatively, I tried to setup DMZ host for my router (192.168.0.24), but still did not work.

Any ideas what settings might be important that I could be missing/setup wrong? I’ve been using an online open port checker tool, as well as trying to access the server using my public IP, but no luck.

On the router and modem side I could not find detailed logs on the traffic, so I’m not sure how to even debug which of the two devices is the problem. Any help on this front would be appreciated.