ARDUINO saves RFID information and a stopwatch TIME to SD card

My problem is that, I use RFID keys and try to save game TIME, with the, same time. I think

The idea of the game is that, the player comes in, and registers his RFID key, then presses the start button, then the stop button and the game saves this elapsed time with the RFID key do the SD.

The servo is not important.
Everything is matched using a copy, paste method.
Everything works until the stopwatch. It’s very fuzzy from there.
If anyone has a better idea then I look forward to it.

I’m using Arduino NANO and its memory gets full so something needs to be deleted. I think.

sketch_sep23a.ino (26.8 KB)