How to create API from allready existing collection

Hello, we have a collection that we want to convert to API. I have found transmatic but does not properly convert the collections output into a importable openapi 3.0 format

Does anybody knows how to do this?

APIMatic Transformer can help here - It converts a Postman Collections V 2.0, 2.1 as an input format and transforms Openapi 3.0 format as output.

Useful Links: