Getting a Mac into DFU Mode is very tricky. You must follow Apple's instructions exactly ....this includes the timing of the key presses and also the cable & ports used on the "broken" Mac. The "broken" Mac must be completely powered off before you can even initiate the key presses (all cables need to be connected first since connecting them can power on the Mac). Unfortunately it is very difficult to confirm these newer Macs are completely powered off.
Also, the host Mac where you are using Apple Configurator must be running the latest version of Apple Configurator which I believe is v2.18 or v2.19 and it does require the host Mac to be running macOS 15.x Sequoia (even when using Apple Configurator). It is best to have Apple Configurator open prior to initiating DFU Mode so you have a little bit of feedback within the Apple Configurator app (or Finder) to tell when the "broken" Mac enters DFU Mode or when it is powered off, or some other intermediate state.
There are times when it takes me six or more attempts before I'm successful.....and I know what I'm doing.
It is also possible the Mac has a hardware issue which is why this is failing.