Why does Fishbowl say "The quantity cannot be negative."?

You've entered or are trying to set a quantity to a negative number. Fishbowl inventory quantities must be zero or positive because you cannot have negative stock.

Fishbowl: "The quantity cannot be negative"

What it means

You tried to enter a quantity value less than zero, or an operation would result in negative inventory. Fishbowl blocks this because physical inventory quantities cannot go below zero.

What to check

The value you entered: Is the quantity field showing a negative number? If so, change it to zero or positive.
The operation amount: If you’re adjusting or transferring stock, verify the quantity doesn’t exceed current on-hand stock.
Whether the operation is reversing correctly: If this is a return, receipt cancellation, or correction, check that the amounts match what actually happened.