Wondering if anyone has got this router/AX series and got wifi calling working?

If I set the operation mode to Access Point and hook it up to my old DLink router, wifi calling works fine on my android phone (at all times).

If I let the AX1800 do the routing and switching, no matter what settings I change, I can never get the wifi calling working.

Honestly I would gladly use the AX1800 as an AP if not for the fact that my old DLink router is very slow (7 years ago) and brings my 1 Gbps connection down to 300-400 Mbps. Other than this wifi calling issue, the AX1800 fits my every use case.

I've been trying to troubleshoot for a few months on and off now, reading off posts from TP Link forums from the past few years, and honestly at this point, I'd rather sell this router off and get another reliable brand in the same price range.

Tried :-

- DHCP Reservation for my android phone

- Port Forwarding (Port 50, 500, 4500, 143, 993)

- Port Triggering (Port 50, 500, 4500, 143, 993)

- Toggling uPNP

- Toggling SIP ALG

- Toggling IPSec Passthrough

- Changing WAN DNS

- Toggling TWT + Toggling Airtime Fairness

- Changing DTIM Interval from 1 to 4

- Factory reset

- Port Forwarding + Port Triggering

- Port Forwarding + Port Triggering + Toggling SIP ALG

- Port Forwarding + Port Triggering + Toggling SIP ALG + Disable IGMP Proxying

- Listing my android phone as a DMZ device