“Multipart body must have at least one part”

Question

In previous asked question (react-native upload pictures on android) described request with param \"FormData\", but I requested GET request without data and got same message

Answer 1

Multipart body must have at least one part. This message is about wrong arguments for fetch function passed from JavaScript code to alternative function in Java.

I tried to pass body as empty FormData, so message about body without any part of it.