I'm going to take that a little further and say that all your tables are improperly linked.
1. ID is a poor choice for a name. Rename ALL the ID fields to something meaningful such as PaymentID, QtyID, etc.
2. Make sure that the foreign keys are defined as long integer because they need to hold the autonumber value, NOT the text value.
3. Use the same name for the foreign key and primary key names to make it easier to see the relationships by just looking at the table layout.