MATLAB: Using dlmwrite to save data

My dlmwrite function seems to not be able to run. To my understanding, dlmwrite is used to write a new .txt file containing the data of interest, right? When I try to dlmwrite, it says I have too many output arguments.
My code: https://pastebin.com/
The original script integrates data of tea spill that I read in (TeaSpill.txt), and I'm trying to use dlmwrite to write another .txt file of the spillLength values as more of an exercise to using dlmwrite. The code works perfectly fine up until dlmwrite. Can anyone tell me what I'm doing wrong? Thank you.
Shouldn't be pertinent but this is the TeaSpill.txt: https://pastebin.com/hVPssVdw
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My output:
Area of tea spill: 88.278 cm^2Error using dlmwriteToo many output arguments.Error in HW6ProbEC1 (line 20)spillData = dlmwrite('spillData.txt',spillLength,'delimiter',' ');>>

spillData = dlmwrite('spillData.txt',spillLength,'delimiter',' ');
dlmwrite('spillData.txt',spillLength,'delimiter',' ');