Hi Sudip,
Please put breakpoints in below Exits/Badi's and check if any one of them triggers before save:
Enhancement
FTRINCON User exits for confirmation status
RFTBB001 Treasury: Posting interface
RFTBB010 Treasury: Posting Interface Due to Cust.-Spec. Acct Determtn
RFTBB011 Treasury: Post.Interface due to SCB Indic. and Deliver.Cntry
RFTXX301 Customer Exit mt300 header
RFTXX302 Customer Exit mt300 trailer
RFTXX321 Customer Exit mt320 header
RFTXX322 Customer Exit mt320 trailer
SAPMFTD1 User Exit Treasury data carrier management
Business Add-in
FTR_TR_FIMA_CALLBACK Determine Proportion of Interest for Capitalization
Thanks
Sri