If creating orders in your development store recently stopped working and you have followed the instructions on this page then the answer is to contact partner support. They will just re-enable it.
Recently creating orders on some of our development stores stopped working. We were receiving messages like the ones below images via Shopify Admin and the stores shopfront.
After days of frustration of here and a number of threads, the consistent answer was you can only create orders via the shopfront and you must have enabled a) A Bogus gateway, or b) Shopify payments in test mode.
I had ALREADY done this and despite posting images showing the error the treads were being marked as solved and locked.
In the end I reached out to partner support and it was fixed instantly..
Frustrating but at least we can get back to writing code and testing.
YES was a genuine issue that can be fixed. If you reach out to partner support do them a favour and make sure you have already followed the instructions mentioned above. Which I am sure you are more than capable of doing as we follow Shopify docs every day.