Web Service Data Adapter is not returning JSON Data in 6.16 but works in 6.9

Trying to call a REST API / GraphQL POST or GET query via Jasper Studio,  using Web Adtapter plugin of version 1.5, returns "Loading JSON Data"... , when click on "Get Responce" button in "Fields:" tab  that never returns any data  in Jasper Studio Community of version 6.16.

While exactly the same data adapter (1.5 is the last version from 2017) returns data in Jasper Studio 6.9. Same happens in Professional version , trial.

is there a way to understand why and where it fails, and how to resolve the problem?

i could not find yet if this is already reported issue.

Also is there any alternative adapter that can be used instead in versions >=6.16?