Net price must be greater than 0 in PO when doing PO release.

[praveendiwan]

Hi Experts , 

We have custom transaction to Release Po Same as ME28 Just added Plant as field so get Po Plant wise so user can approve them . 99% of time we didnt encounter issue while release via this ZXXX Po release T Code 

we are facing problem that when we are trying to release level 2 ( Release Code ) we are getting message " Net price must be greater than 0 in PO when doing PO release."

Firstly Po was completely released then We have done GR IR on PO for some quantity . 

When User Try to add line 20 on PO to add extra qty on fully releases on then due to change in Po new release strategy determined & again it has gone for approval .

Users didn't delete conditions in any of the PO. In case, already approved PO needs more quantity, user adds new line and resends PO for approval after he does first level of approval. 

While releasing for first time user able to release Po at Code N1 , but when user tries to release Po at Code N2  after fully released we get following issue in PO.

1) Error - "Net price must be greater than 0"

2) Conditions are zeroed out on item and header level for all item line 10 & line 20 

3) Header Data Changed after Release by Level N2 It has mixed with Other Po Data .

Field changed ex : Company Code, Purchasing Group, Purchasing Organization, Release Indicator: Purchasing Document, Release Strategy, Supplier's Account Number Different Invoicing Party, Currency Key

This is happening in some cases only not for all Pos .One condition is same in all cases that when user tries to add new line item under already released PO this scenario happens & Also it is happening at Release Level -2 ( Release Code ).

Please  help me to know root cause of this issue , why the conditions are being deleted for line items under Po ?

Thanks in Advance