once in a lifetime
And one very important update here. CTCSS decoder may not work in your AT-500M radio, as well as it may not have 24V to 12V DC-DC stepdown converter. Just not soldered on PCB at all, yet the store page says it is an 'optional'. How the hell it can be an option? Will they send me a kit to solder myself? Just wondering.
Let's get back to a CTCSS thing. You can still select CT in a menu, you can still set tone and even encode this tone into your signal while TX, but... the radio will stop receiving anything because it cannot decode any tone. It will just remain silent no matter of signal strength, while any other radios with T-SQL will sound.
I have 4 rigs total, 2 of them is called 'Track Barry' and is branded for russian market. And other two is pure AnyTone AT-500M from Aliexpress. Those russian versions is perfectly fine with CTCSS and 12/24 DC-DC, yet Aliexpress things are not. Sad story.
China. It is always something in there. If you think there is not - you've just not found it yet.