It will be better, if you take take help of ABAPer in your team.
There are fair chances that this could be due to some enhancement done on program SAPLV45U - Sales: Update Program. Already 2 enhancement
ENHANCEMENT 2 OI0_COMMON_SAPLV45U. "active version
ENHANCEMENT 3 OI0_COMMON_SAPLV45U. "active version
visible on the code shared by you. Both of them are related to pricing.
Thanks, JP