Firmware for RG500L-EU

Hello,
I have a router running the RG500LEUACR04A01M1G firmware.
Recently, I encountered an issue with the 5 GHz Wi-Fi: whenever a device tries to connect to this band, the router automatically restarts.
This issue didn’t occur before.
I’ve already tried resetting the router, but the problem persists.
I believe flashing the firmware might help resolve this.

Could you please provide me with the correct firmware for this device?
I have already downloaded QFlash_V7.4 to perform the update.
Thank you in advance.

Dear @odilonse
RG500L is open solution, other engineer will help you.
@Bryan.Tan-Q Please help to check.

Hello,

Please help to provide the firmware info, you can send AT+CGMR and AT+QGMR to get the info