Problem with MJpeg

We tried to use the MJpeg stream in our application but the player returns the error “Content-Length must contain only digits”.

This same error also appears when simulating with Postman, so it does not depend on the player used.

The Mjpeg stream works when viewed in a web browser but does not work on iOS. It is necessary to correct the content-lengh that is being sent with invalid characters.
Is it possible to make this correction?

We have a license with 64 cameras and we intend to buy more licenses because we have many more cameras but we need this integration with our app to work.