ok if I understood your router is still updating your DDNS IP if needed. Correct? If yes, thats fine and no need to change anything on this.
Now, to fix access locally, you would need to set a custom DNS entry inside PiHole to point to your local system.
- open PiHole
- Local DNS
- DNS Records
- Domain: your.ddns.com
- IP Address: 192.168.1.15
- Add
This will save the entry and your clients should resolve your ddns locally with the IP address of now. You could test as follow if you have a Windows client
nslookup your.ddns.com