Stripe is not working because server is not recognising Pending Orders.
{
"errors": [
{
"status": 409,
"source": {
"parameter": "id"
},
"title": "Conflict",
"detail": "You cannot charge payments on a cancelled, expired or completed order"
}
],
"jsonapi": {
"version": "1.0"
}
}

Refers fossasia/open-event-frontend#3712