Error: Mismatch between sold and purchase quantity

You add a product, click Pay, and the sale is refused with:

ERROR: NOT ALLOWED: Mismatch between sold and purchase quantity. Product: … SKU: … Quantity: …

Why it happens

TechFusion POS keeps two records for every stocked product:

1. The stock count shown in the POS and product list.
2. Where that stock came from: the purchases, opening stock and stock transfers that brought it in. Every sale is matched to one of these (first in, first out), which is how your profit and stock value are calculated.

The error means the stock count says you have the item, but there's no purchase or opening-stock record left to match the sale to. The two records no longer agree, so the sale is blocked rather than recorded wrongly.

The usual causes:

• The product's stock was entered without opening stock or a purchase, for example by an import that failed halfway, or a purchase that was later deleted.
• The lot / batch with that stock has expired and Stop selling expired stock is on. The message then ends with a note about expired stock.
• The stock is at another location than the one you are selling from.

How to fix it

1. Check the location

Make sure the POS is on the location that holds the stock (top-left of the POS screen). See Products › List Products › Actions › Product Stock History for each location.

2. Expired lots

If the message mentions expired stock, either sell from a newer lot, or record the expired items as a Stock Adjustment and receive fresh stock with a purchase.

3. Stock without a purchase or opening stock

Give the existing stock a source, then remove the duplicate count:

1. Products › List Products › the product › Actions › Add or edit opening stock. Enter the quantity the system currently shows, with its cost price, and save. The stock count now shows double.
2. Stock Adjustment › Add. Choose the same location and product, enter the same quantity, with the reason "Correcting stock records", and save. The count is back to normal, and now every unit has a source.

Try the sale again. It will go through.

4. Still blocked? Contact support

If several products are affected, or you're not sure, contact support with the product name, SKU and location from the error message. Our team can rebuild the stock records of your whole business in a few minutes from your own sales and purchases. Your sales history is not changed.

Avoid it in future: always add stock through Purchases (status Received), Opening stock or Stock transfers, never by editing numbers directly. Don't delete a purchase whose items have already been sold.

Related: Stock looks wrong