Hello TP-Link Community,

I'm experiencing an issue with my new NX600 router regarding the failover functionality between my fiber connection and 5G backup.

Configuration:

• I followed the official guide to set up 5G as a backup connection: https://www.tp-link.com/fr/support/faq/4793/
• Primary WAN: Fiber connection
• Backup: 5G mobile network
• Failover : EWAN selected in WAN Priority

The Problem:

A few days ago, I experienced a fiber outage. The router seems to have successfully switched to the 5G backup connection. However, my entire 5G data allowance (300GB) was consumed during this period (I've reached my data limit), and the connection is now "throttled" by my carrier.

Since the fiber connection has been restored, the router appears to have switched back to fiber (the public IP shown on websites matches my fiber connection), but internet performance is extremely slow on all devices in my home network.

Current Situation:

• Public IP = Fiber IP (failover seems to have occurred)
• Speed tests and general internet access = extremely slow
• Workaround: When I manually disable the 5G connection in the NX600 settings, speeds immediately return to normal

Questions:

1. Why doesn't the router properly release the 5G connection after switching back to fiber?
2. Is there a known bug with the failover mechanism (or others mechanisms) that causes these issues?
3. Should I perform a specific action?
4. Has anyone experienced a similar issue?

Any suggestions would be greatly appreciated.

Thank you in advance for your help!

Router Model: TP-Link NX600
Firmware Version: 1.2.0 3.0.0 v60ec.0 Build 250806 Rel.41198n
ISP: Orange (France)
Mobile Carrier: Bouygues Telecom (France)