Short answer
If a subscription payment fails, Lancer pauses your campaigns so nothing runs on an unpaid plan, and you'll see a payment-failed notice on the Billing page. Update your payment method and, once the payment goes through, the campaigns Lancer paused start again on their own. Don't leave it unpaid: if the invoice is still unpaid after 3 days, the subscription is cancelled.
How to fix it
Open Settings → Billing.
Click Manage in Stripe and update your card or payment method.
Once the payment goes through, the campaigns that were running when the payment failed restart by themselves. You don't need to toggle them back on.
Lancer only pauses campaigns that were running when the payment failed, and only those restart: campaigns you had paused yourself, drafts and archived campaigns stay as they were. If a campaign can't restart (for example its Upwork account was disconnected in the meantime), it stays paused; fix what it needs and turn it on from Campaigns.
Common causes are an expired card, insufficient funds, or a bank declining the charge.
What happens if it stays unpaid
Lancer cancels a subscription whose oldest unpaid invoice is 3 days overdue. The cancellation voids the open invoices, so nothing keeps charging you afterwards, and your organization is marked cancelled: campaigns stay paused and your connected Upwork accounts disconnect. To come back, subscribe again from Billing. See "How to cancel, pause, or downgrade your Lancer subscription" for what is kept.
Pay-Per-Lead: unpaid overage invoice
On Pay-Per-Lead, the first failed overage invoice is only a warning. If a second one fails and both are still unpaid, the app is locked the same way as a failed subscription payment: you're sent to the Billing page, and the only thing you can do is pay. Your running campaigns are paused while the app is locked. Update your payment method via Manage in Stripe and settle the invoices; access comes back once they are paid, and the paused campaigns restart by themselves. An overage invoice that has been voided or written off also lifts the lock (checked hourly).
Already updated your card in Stripe, but it's still failing?
If you changed your default card in the Stripe billing portal but the charge keeps failing on your old card, you shouldn't need to do anything else. The next time we attempt the payment, Lancer automatically detects that your subscription is still pointed at the old card, switches it to your current Stripe default, and retries the charge right away.
Once that retry succeeds, your billing status updates automatically and the paused campaigns restart by themselves, same as step 3 above.
If it still won't go through after that, message us.