Price unit & is not supported

What causes this issue?

You entered the invalid price unit &V1& in period &V2& for cost center/
activity type &V3&/&V4&. Only the values 1, 10, 100, 1000 or 10000 are
valid for price units.

System Response

The value for the price unit was not accepted.

How to fix this error?

Enter only the above specified values for the price unit.

Error message extract from SAP system. Copyright SAP SE.