I am attempting to test credit card payments in my sandbox merchant account using the v2 `/pay` endpoint, but I'm getting an `"Unexpected 'E'"` response back when making the requests with Postman - which I am _guessing_ (based on reading other posts) actually indicates a `503 Error connecting to Payment Gateway` response.
I am following the documentation here:
https://docs.clover.com/build/developer-pay-api/, and have tried posting payments using these test cards
https://docs.clover.com/build/simulate-transaction-scenarios-partialdecline/ as well as with some real cards.
Here is my process:
1. Successfully create an order with `POST /v3/merchants/{mId}/orders` (with minimal body like: `{ "state": "open", "total": 200}`)
2. Encrypt card number for `/pay` request using data in response from `/v2/merchant/{mid}/pay/key`. I'm pretty certain that I am generating the `cardEncrypted` string correctly following the these steps:
https://docs.clover.com/build/developer-pay-api/#e...
3. Make a POST request to `/v2/merchant/{mid}/pay` referencing the order from #1 with body such as:
```
{ "orderId": "9CV07JMPX4S74", "zip": "22204", "expMonth": 9, "cvv": "123", "amount": 100, "currency": "usd", "last4": "4242", "expYear": 2020, "first6": "424242", "cardEncrypted": "base64_encrypted_string_from_step_2"}
```
The `/pay` request takes about 30 seconds to process before returning the error. I'm new to Clover APIs so forgive me if I'm missing something fundamental here such as not being able to process transactions in this way against a sandbox account. Or, perhaps I need to have clover hardware set up in order to process payments? I have not ordered a dev kit yet. Thank you in advance for any help.