Uploading image with parameters (Alamofire)

I am attempting to upload an image (avatarImage) to the server as a formData parameter type using AlamoFire, but I am generating a "The data could not be read because it isn’t in the correct format" error every time I attempt to post. What am I doing wrong?

class func createTeamWithAvatar(avatarImage: Image) {
    let extendedURI = "\(RequestManager.baseURL)" + "\(RequestManager.ClickUpURI.Team.rawValue)"
    RequestManager.sharedAlamofireManager.upload(multipartFormData: {
        multipartFormData in

        //This generates an error: "The data could not be read because it isn’t in the correct format"
        if let imageData = UIImageJPEGRepresentation(avatarImage, 1) {
            multipartFormData.append(imageData, withName: "avatar", mimeType: "image/jpeg")
        }
           
        }, to: extendedURI,
            encodingCompletion: { encodingResult in
                switch encodingResult {
                case .success(let upload, _, _):
                    upload.responseJSON {
                        response in
                        
                        if let statusCode = response.response?.statusCode,
                            let response = response.result.value as? Dictionary<String, AnyObject>,
                            let _ = response["id"] as? String
                            , statusCode == 200
                        {
                            completionHandler(response, nil)
                        } else {
                            let responseError = response.result.value as? Dictionary<String, AnyObject>
                            
                            let errorInfo = responseError ?? ["err" : "Unexpected media uploading error" as AnyObject]
enter code here
                            let error = response.result.error ?? RequestManager.makeError(response.response?.statusCode ?? 500, userInfo: errorInfo)
                            completionHandler(nil, error as NSError?)
                        }
                    }
                default:
                    completionHandler(nil, RequestManager.makeError(500, userInfo: ["err" : "Multipart encoding failed" as AnyObject]))
                }
        })
    }

PS: I am using multipartFormData to upload because I need to send some other parameters as well (once I am able to upload an image).

I had to add .httpAdditionalHeaders b/c my server was expecting certain data:

RequestManager.sharedAlamofireManager.session.configuration.httpAdditionalHeaders = ["Accept": "application/json", "Content-Type": "multipart/form-data"]

You can add more configurations by appending a key/value pair to this array.