Price condition not found: &, agreement: &, item: &, date: &.

What causes this issue?

You have filled an invalid date on <LS>Valid From</> and <LS>Valid to</>
fields.

System Response

Once you have filled the correct dates, the system searches in
customizing the Gross Price and fills automatically the Amount field,
according to the information registered for a specific period. If you
fill the <LS>Valid From</> and <LS>Valid to</> fields with a date that
has not been registered on the system, it will provide you an invalid
value.

How to fix this error?

Please check the dates you have filled on <LS>Valid From</> and
<LS>Valid to</> fields and use the correct information.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.