Possible reasons:

• amount must be positive
• could not parse amount: {body.amount}
• transaction with this external_id was already attempted
• unknown asset_code
• unknown recipient

Not authenticated

the authority account cannot be used as the account for a transaction

Not found

recipient is archived

The request body is valid JSON but does not match the expected schema.

Possible reasons:

• attempt to verify existing contract failed
• could not begin transactional query
• database error
• failed to build contract
• failed to commit database transaction
• failed to create transaction
• failed to get asset code
• failed to save contract