Hi there Nuthatai,
this is a common enough bug only identified after upgrade to 7.3, please implement the correction instruction and see the manual steps in the following note to resolve the issue...
1709947 - SP29:Field length wrong in source and target of TRF
The report ZRSTRAN_CHECK_STEP_CONSTANTS will identify both the transformations affected and the inconsistent rules in each.
Best Regards,
Colm