我无法摆脱请求失败：错误请求（400）

NSDictionary *parameters = @{
                             @"project_name": @"hasanProj",
                             @"project_desc" : @"testing...",
                             @"project_date" : @"2015-2-22"
                             };

AFHTTPSessionManager *manager = [[AFHTTPSessionManager alloc]initWithBaseURL:[NSURL URLWithString:@"https://serverIP"]];
manager.responseSerializer = [AFJSONResponseSerializer serializer];
manager.requestSerializer = [AFJSONRequestSerializer serializer];
[manager.requestSerializer setValue:[HRUser sharedUser].userApiKey forHTTPHeaderField:@"Authorization"];
[manager POST:@"/rest/v1/project" parameters:parameters success:^(NSURLSessionDataTask *task, id responseObject) {

    NSLog(@"%@",responseObject);

} failure:^(NSURLSessionDataTask *task, NSError *error) {
    NSLog(@"error: %@",error.localizedDescription);
}];
NSDictionary *parameters = @{