The team has gone read-only
A lapsed trial, an unpaid subscription, or a closed team. Nothing has been deleted.
First, the important part: nothing has been deleted. Your roster, expenses, payments and ledger are exactly as you left them, and you can still read and export all of it. There are three reasons this happens, and a banner at the top of the page says which.
This team is read-only. Your free trial has ended — nothing has been deleted, and subscribing puts it straight back to normal.
The free trial ended
Subscribe from Settings → Billing and everything returns immediately. See the free trial.
The subscription lapsed
Usually a card that expired. Update it through the billing portal. Stripe retries failed charges for a couple of weeks before access is affected, so this rarely arrives without warning.
The team was closed
Someone chose to close it — the normal end-of-season move. Reopen it from Settings; it's reversible and billing restarts.