TP-link RE450 : 5ghz access point not broadcasting SSID

My 5ghz master lan wifi network stopped broadcasting after 1 week of not using the device, had to create a 2.4ghz. Any leads on this issue ?

Looks like the "Livebox" the client interface is connected to moved to a DFS channel, channel 60. Simultaneous client and AP is not possible on a DFS channel.

Thanks, how to solve this ?

If you control the "Livebox" AP, configure it to operate on a non DFS channel. If you can't change the channel at that end, there's nothing you can do.

While using a DFS channel is more fragile, I've been using that successfully with qca9984 and ar9380 or qca9888 for quite a while now.

Those are wave 2 chips-- there may be a difference. In a release version I've never had it work on ath9k or ath10k (wave 1 CT). I don't have any wave 2 chips to try on.