My modem is connected to external provider (Leaptel) for sip phone. When I call my number it rings just twice and ringing stops but line is active - I can pick the handset and call is made.

Phone is basic Uniden FP1100BLK, connected to modem directly. Also tried another handset and same issue with that phone as well.

I saw old thred on tplink where people facing same issue, and resolved by either changing some settings or mainly downgrading the firmware.

Ref link: https://community.tp-link.com/en/home/forum/topic/773718?sortDir=DESC&page=1

I tried to download the firmware and downgrade. on TPLink there are 3 firmware available but I was only able to downgrade to 1st one but other two old one didn't work for me. It was giving me error.

But my concern is if TP Link already got this issue raised by other people in past why there is not solution with latest firmware.

Please provide me zip upgrade files last 5 firmware for my model so I can try one by one. and if u have any solution already please let me know.

Firmware Version:  0.14.0 2.0.0 v6092.0 Build 250417 Rel.24761n

Hardware Version:  Archer VX1800v v1.0 00000000

Serial Number:  22513M3002980

Thanks