My TV can't find the channels.

Give me the location of residence so I can see which transmitter you depend on and what "My TNT coverage" says about it.

You mention an antenna with an amplifier... this amplifier is probably electrically powered. Have you checked that this power supply is functioning?
Is the antenna properly pointed (like your neighbors') in the direction of the strongest transmitter indicated by "My TNT coverage"?
Also check that the antenna cable is properly plugged in, both at the television end and at the wall socket.

I've already done a search with my address, it's good.
The amplifier is green, it's good.
The antenna plugs are well positioned.
If the antenna is pointing well, I don't know ... oops!!!
Would it be useful for me to buy a decoder or can we find an amplifier to put in the house????
Thank you
For now, I'm losing my mind, I'm going to install my Orange TV decoder that's in my room while waiting to find a solution.
If buying a device can solve my problem, please let me know.
In any case, thank you for your kindness and your patience.
Best regards
Coco

you really don't want me to check for myself what "My TNT coverage" says

if the antenna is pointing correctly, I don't know
You just need to see if it seems to be pointing in the same direction as that of your closest neighbors.

you say an amplifier already exists.. check that it is powered on

Buying a decoder will do no good, your television is indeed compatible with the new standard

I did it, thank you, now I just need to have an antenna technician come by.
I connected my Orange TV decoder in the living room, it works.
In the bedroom, I don't have a TV anymore...
Thank you and have a great weekend
Best regards
Coco