Contract End Date is not getting copied for specific line item

I'm trying to update the Contract end date at header level and ideally same should be updated at the line item level. This is happeneing succesfully for one contract and SKU combination but it is not happening for a the same SKU in a different contract.

For the contract in question, other line items got updated succesfully except 1 SKU.

All header details and dates are similar including contract type/item category/SKU, etc.