Try adding STRDLM(*NONE) to your CPYFRMIMPF command. The default is STRDLM(*DBLQUOTE) and there are no quoted columns in your sample.
I would first guess that the command looks at the first portion of the first row and sees [S0100113]. Since it doesn't find any quotes, it tries to generate a numeric value.
I don't recall a delimited file that didn't include any indication of which columns were strings and which ones weren't, so this might take some experimentation. It's possible that this format is outside of what the basic CPYFRMIMPF function can handle.
I believe the message is stating that one of the ‘columns’ in your input text file contains blanks or alpha characters that you are trying to feed into a DB2 file that has that the field defined as numeric which is not allowed.