Arduino SD Writing

Hello, I am fairly new to the arduino world. I am currently working on a data acquisition logger that writes to an SD card module. The logging code works, but I need to have the module write “new” each time the arduino is powered on to the SD card. It needs to be written once, so I have been trying to put it in the “void setup “ section of code. I just cannot seem to get it to work. Any suggestions? Example codes?

Example codes?

Your code ?

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add fpmDATA.close() after "writing new"