Clean install 8.0 version is solve this problem ! Update from 7.** not ...
Everyone if you have some problem with some gamepad - try to recalbox 8 version ..

@zing I dont think so .. This game pad works normaly in game after reconnect (hold start button is off goy and then on again) after that in this game is OK!!

Today i test it like second gamepad, first gamepad was "Wingman USB gamepad" soo, like second gamepad its OK from start, and dont need reconnect it ...

Soo..
I test for this bug all versions of 7 release..
"Good" work only one 7.0.1. After start game any buttons doesent work, but if i reconnect gamepad without exit game, all buttons is OK even if enter retroarch.. Next game - same trouble..
I'l test it bug on
7.0
7.0.1
7.1
7.1.1
and all of 7.2 versions
(I use it on Rpi3b+)

Some new..
7.2.2 and 8BitDo M30, after start any game i have "dead" gamepad, but if i reconnect it to Recalbox, and no exit of game - all functions is works! But if i enter to nestopia (special key and B button), i have doesnt work gamepad again ...
How to fix it? Anybody knows?

@zing Of course .. sorry ... my mistake ... 7.0 version ...

This gamepad has 3 global modes (Android, Windows, MacOS) If i connect it to RB 7.2.2 like "Android" it works in main dashboard and in Kodi menu but "dead" in game mode in all emulators.. "MacOs" mode doesnt recognize of this version recalbox. And mode "Windows" is OK only if you activate GPIO-controller in "WebFace" but very long time starting game. Previously on version 6.0 of recalbox is OK in everything mode.. Even if i install 6.0 version and upgrade it to 7.2.2 from menu (Not clean install 7.2.2) M30 still works in "Android" mode.. Something "new" broke old stabile..
Sorry for my english, i hope are everyone understand me..