r0an
Should you mean the cancellation date shown under ‘My Services’ on swisspass.ch:
I think this one keeps showing the cancellation date for the current period as long as you technically still could cancel by end of that period (and get the already paid following period refunded). In other words, that date should update to 2026 once the displayed 2025 date has been reached.
As long as in the account statement under ‘invoices’ you can see a 0.00 balance and a recent payment receipt entry, everything is fine.