This is already pretty helpfull, thank you.
I've tested some settings and when setting the Matrix Header Value Line # different changes the outcome.
#0: no lines were accepted (12 header rows have error code 4, all other lines 11)
#1: 12 lines are accepted (all not accepted lines have error code 11)
#2: 23 lines are accepted (1 header row is getting error code 4, rest has 11)
#3: 34 lines are accepted (2 header rows are getting error code 4, rest has 11)
#15: 166 lines are accepted (12 header rows are getting error code 4, rest has 11)
#100.000: 385 lines are accepted (35 rows are getting error code 4)
When I change the amount cloumn in the last scenario from 0 to 8 (the 2025M1 column), the amount of accepted lines won't change, however the error codes do. Now there is 1 error code 4 and the rest is 11.
--------------- Log Codes ---------------
Non-Numeric Amount ..................... 4
Time Outside Workflow View.............. 11
Transformation Rules shouldn't be a problem, because I'm uploading a file with OneStream time dimensions (2025M1, 2025M2 etc.). I have also added one-to-one transformation rules for all seperate months, but it didn't give another outcome.
Can't get my head around the issue, however maybe the test above gives you any clue on where the issue might be?