IFormFile object in API controller is null

[Laith-Saed]

Hello, I'm trying to send IFormFile from razor post form, to a web API project. The controller API method is being called successfully but the object that is passed to API controller from razor view controller is null "IFormFile object".
What should I do ?
EDIT
I Tried the AddContent, and AddFileContent methods, and nothing worked. I tried to add the IFormFile object in an object of class, and in the method parameters, in first one all the object is null, and second one only IFormFile is null.