Sorry about this! This is a known issue that is already being addressed, it can occur when the payment form fails to load (usually due to an ad blocker, privacy extension, or corporate firewall blocking the Stripe payment iframe).
Please try:
1. Disable any ad blockers or privacy extensions (uBlock Origin, Privacy Badger, etc.)
2. Try in an incognito/private window
3. Make sure third-party cookies are enabled
4. Try a different browser
If it still doesn't work, email [email protected] and we'll get you set up directly.