The "Blank Subtraction" option is not active


I try to process my LC-MS spectra on MetaboAnalyst.

I have 12 Spectra: 3 Blank, 3 QC, 3 Controls, and 3 Tests. When I try to subtract the background feature from my spectra, I always find the option “Blabk Subtraction” is disabled and inactive, as in the attached picture. Could you please help me to get this option activated?

BTW, I have uploaded the blank spectra and given them names starting with “Blank_”, and I also have labeled them as “Blank” in the metadat.txt. file, just as instructed.

Many thanks to you in advance,

See below on the instruction (note QC, BLANK):

Thank you so much. It now works. I should have written “BLANK” instead of “Blank” in the metadata.