PUR500 cannot maintain lines - Line 001 due date may not precede entrydate

Hi,
we are on 6.101

we tried to open order in PUR500 because we needed to close by 16 some
order lines, we are using purchase contracts (orders are created by
Scheduled PO Batch Release PUR651D)

but we cannot close historical maintain lines in because of message - Line
001  due date may not precede entry date

I found that it is doing in case purchase price is not entered in PUR150
for contract, but even we enter it after we cannot maintain the purchase
order in PUR500

I was comparing ECL ECH to orders without problem, no diference

How to close order line in this case? Why this message, I am thinking hat
in case the price is missing it is validating the line like entered
manually, but when I enter price by SQL to HPO still the same problem....

have a nice day

Michal Jablonka