Mark rent received, and send a reminder when it has not arrived.

Open a property's Finance tab and click Rent status (or click the property from the portfolio Rent status page). This is where you record a rent payment and, if it has not arrived, send a reminder. The picture above shows it.
The Chasing panel shows every reminder already sent and when.
When the balance has not moved, it recommends sending another and gives you a Chase rent button — one click sends the tenant a reminder in your name.
You are never chasing blind: the history is right there, so you know whether this is the first nudge or the third. The days late in a reminder count from the oldest rent still unpaid.

The Payments table lists each period beside what was due, what was paid, and its status — received, part paid, overdue, or not recorded (a period before the tenancy's tracking start, which is not counted).
To log a payment, use the Action button on that period's row and choose Record payment, then enter the amount that actually arrived — not the amount due. The outstanding figure drops by what was paid, any open chase closes once the balance clears, and the payment flows into the property's Finance and your tax estimate.
A part payment is recorded as what came in; the rest stays on that period's balance and carries forward.
Recorded the wrong figure? The same Action button offers Un-mark as paid on a period already marked received.
If you joined part-way through a tenancy, you may have many months to catch up. Choose Action, then Mark several paid. Tick the months, or use Tick all, then select Mark paid. On a phone, tap a month and choose Mark several paid there.
We ask Were all [number] months paid in full? Mark paid in full records each month as received on its due date. Mark partially paid lets you type what you received for each, with £0 for nothing. These count as real income in Finance and your tax estimate, so only mark what arrived. It also works on a room's own page and on a shop lease's quarters.