Help required for quotation to sales order item table rates error

Recently we are encountering following error in my erpnext V13

  1. when a quotation is prepared, say customer1, with 5 items with discount 45%, say total value is 550/- (example)

  2. when sales order for customer1 after confirmation is now having value as 550/-

  3. now as per customer1, we slightly change the name of customer as per his request to customer2

  4. entire item table has no effect of discount, total value of Sales Order is shown as 1000/- (example) ignoring 45% discount for all items

  5. no use of reversing even if we change back party from customer2 to customer1

earlier this issue was not there, it use to smooth flow… quotation - to sales order - to sales invoice

i am stuck