Understand the installment schedule

Saving a pledge generates its installments. Open any pledge to see them.

The schedule

The Installments section of a pledge showing a summary line and a table of installments with due dates, amounts and statuses

The summary line (A) gives the count and the per-installment amount at a glance. In the table (B), each row is one expected payment: its number, due date, amount and whether it has been paid.

Two different statuses

The Status and Payment Status fields on a pledge form

These answer different questions and it is worth not conflating them:

Status (A) is the state of the commitment itself: active, completed, or closed.
Payment Status (B) is whether it is keeping up: on schedule, overdue, or paid.

Payment status is derived, not typed. Mich recalculates it as dates pass, so a pledge becomes overdue on its own without anyone remembering to mark it.