Sometimes Smovin assigns a payment to the wrong contract, or a payment captured on your account actually has nothing to do with rent. From the reassignment window, you can either link it to the correct contract or take it out of rent tracking.
Open the reassignment
Open the relevant contract, click the Financials tab, then stay on the Transactions details view.
Find the line of the payment concerned.
To the right of the line, click the ⋮, then Re-assign. The Assign payment window opens.
Case 1 — The payment belongs to another contract
Under Select the contract, choose the correct contract, then click Assign.
Case 2 — The payment has nothing to do with rent
In the "This payment does not belong to any contract" box, click Unassign. The payment is removed from the contract and is no longer linked to any contract. You can find it again in the Transfer history of your bank account, marked Geen Smovin betaling.
See How do I view the history of incoming payments on your bank accounts connected to Smovin?
⚠️ Do not confuse this with a duplicate payment (the same payment entered twice): in that case, delete the line added by hand. See How is a contract's balance calculated?