Subform problem

I have a subform when you click on request,choose store name (safeway), click on the button on the right handside, you will see subform that has some events. Under quantity, not billable unit, not billableamount. to calculate the total at the buttom. Also, when you click on Embreimbitem, It will add separetly in Expensereimbursment amount which is in red. The problem I have is that everytime you add new record, when you get the the third or forth field, the cursor goes to the first record in the first field. I thought of every possible way but was not able to solve it. I attached the database. It was developed under 2003.

Nº del proyecto: #213184

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