To test the payment flow, you can use the following test card numbers provided by Stripe and Lemonsqueezy:

DescriptionCard Number
Visa4242 4242 4242 4242
Mastercard5555 5555 5555 4444
American Express3782 822463 10005
Insufficient funds4000 0000 0000 9995
Expired card4000 0000 0000 0069
3D Secure4000 0027 6000 3184

Do not use real credit card information in the test mode. Use the test card numbers provided to avoid any charges and to avoid getting banned from the payment provider.