basic auth URLSession POST

Hi developers im trying to do a request like my postman using basic auth with an Username & password, but i can't archieve, heres what i have done so far

this is how postman look like

Authorization

-> Type

->Basic Auth
username: example_Username

password: example_Password

Body

-> form-data

KEY: grant_type VALUE: password

KEY: username VALUE: test@gmail.com

KEY: password VALUE: 03ac674216f3e15c761ee1a5e255f067953623c8b388b4459e13f978d7c846f4

first i tryied this way

func postDataFormRequest(resource: TokenRequest, completion: @escaping (Result<Token, NetworkError>) -> Void) {
        
        let headers = [
            "Username": "example_api",
            "Password": "example_api_password",
            "Content-Type": "application/form-data"
        ]
        
//this information comes from TokenRequestStruct once i call it form my VC
        let body = "grant_type=\(resource.grant_type)&username=\(resource.username)&password=\(resource.password)"
        
        guard let url = URL(string: "example/") else { return }
        
        var request = URLRequest(url: url)
        request.httpMethod = HTTPMethods.POST
        request.timeoutInterval = 60
        request.httpBody = body.data(using: .utf8)
        request.allHTTPHeaderFields = headers
        
        URLSession.shared.dataTask(with: request) { (data, response, error) in

            guard let data = data, error == nil else {
                completion(.failure(.domainError))
                return
            }

            let result = try? JSONDecoder().decode(Token.self, from: data)
            if let result = result {
                DispatchQueue.main.async {
                    completion(.success(result))
                }
            } else {
                DispatchQueue.main.async {
                    completion(.failure(.decodingError))
                }
            }
        }.resume()
    }

using this method response =

CredStore - performQuery - Error copying matching creds.

Error=-25300, query={

atyp = http;

class = inet;

"m_Limit" = "m_LimitAll";

ptcl = http;

"r_Attributes" = 1;

sdmn = "oauth2/client";

srvr = "3.216.253.237";

sync = syna;

}

tried to fix it by using arbitrary loads = YES

didn't work

Second way

static func getPostString(params:[String:Any]) -> String
    {
        var data = [String]()
        for(key, value) in params
        {
            data.append(key + "=\(value)")
        }
        return data.map { String($0) }.joined(separator: "&")
    }
    
    static func formData(url:URL, params:[String:Any], finish: @escaping ((message:String, data:Data?)) -> Void)
        {
            var request = URLRequest(url: url)
            request.httpMethod = "POST"

            let postString = self.getPostString(params: params)
            request.httpBody = postString.data(using: .utf8)

            var result:(message:String, data:Data?) = (message: "Fail", data: nil)
            let task = URLSession.shared.dataTask(with: request) { data, response, error in

                if(error != nil)
                {
                    result.message = "Fail Error not null : \(error.debugDescription)"
                }
                else
                {
                    result.message = "Success"
                    result.data = data
                }

                finish(result)
            }
            task.resume()
        
    }

usage:

in my VC

let dict:[String:String] = ["username": view.emailField.text ?? "", "password": view.passField.text ?? "", "grant_type": "password"]

            let url = URL(string: “example”)!
            NetworkManager.formData(url: url, params: dict) { (message, data) in
                print(message)
                print(data)
          

didn't work either it says Mising grant_type

third way:

public static func LoginGenerateTokenPOST(userName: String, password: String, completion: @escaping (Bool) -> ()) {
       let baseUrl = "example"

        
        let url = URL(string: "\(baseUrl)example")!
        var request = URLRequest(url: url)
        request.setValue("application/form-data", forHTTPHeaderField: "Content-Type")
        //request.setValue("application/json", forHTTPHeaderField: "Accept")
        request.setValue("example_api", forHTTPHeaderField: "example_api_password")
        request.httpMethod = "POST"



        let postString = "username=\(userName.lowercased())&password=\(password.sha256())&grant_type=password"
        request.httpBody = postString.data(using: .utf8)
        
        let task = URLSession.shared.dataTask(with: request) { data, response, error in
            guard let data = data, error == nil else {                                                 // check for fundamental networking error
                 completion(false)
                print("error")
                return
            }

            if let httpStatus = response as? HTTPURLResponse, httpStatus.statusCode != 200 {           // check for http errors
                print("statusCode should be 200, but is \(httpStatus.statusCode)")
                completion(false)

               
            }

                do {
                if let convertedJsonIntoDict = try JSONSerialization.jsonObject(with: data, options: []) as? NSDictionary {

                   print(convertedJsonIntoDict)
                    
                    
                    
                }
            }
            catch let error as NSError {
                completion(false)
                print(error.localizedDescription)
            }

        }
        task.resume()

        }

this is my third function didn't work either

so my question is:

what is the best way to use basic auth URLSession POST, what did i do wrong in any of the 3 cases?, or all 3 are useless