BOM change with history requirement

Hello All,

I have a requirement of making BOM changes ONLY with a ECM number, meaning if I try to change BOM without ECM it should throw hard error. Now I have gone to earlier posts and made necessary settings

1)IN OS25 I have maintaine hist req for usage/status 1

2) In OS27 I have enabled hist req with Hist req varint 1 (I have tried all)

3) The authorization object C_STUE_NOH assigned to all roles for transaction cs02 have a value of " " (NO) for field NOHIS

I am still getting only a warning when I change BOM without change number. How do I convert this to error

Atul