The reason u are getting the same answer for the different user, has different problem at its root, as u r using the same name for all the user images, and they just overwrites each other.
The thing about storing them on heroku or somewhere else depends on your use case.
H12(Request) Timeout Error in Heroku on Deployment
That is exactly what I am asking ! Ok , I’ll use some online db for large storage if needed. You can mark the doubt as resolved/closed.