What SD support are you using? SD.h only supports 8.3 style 11 character names. You need to use SdFat.h for long name support.
https://docs.arduino.cc/libraries/sdfat/
What SD support are you using? SD.h only supports 8.3 style 11 character names. You need to use SdFat.h for long name support.
https://docs.arduino.cc/libraries/sdfat/