Example

protected override async void OnResume()
        {
            //Helpers.Settings is James's Settings plugin, this setting with the replaces works in other parts so i have no reason
            //to assume this is the cause
            var req = new RegistrationUpdate()
            {
                SerialKey = Helpers.Settings.License.Replace("/", "").Replace("\\", "").Replace('"', ' ').Trim()
            };

            var stringc = new StringContent(JsonConvert.SerializeObject(req), Encoding.UTF8, "application/json");
            //Just a manager that uses a httpclient to stick getKey behind our API's URL and make a post request with the stringcontent
            //as the post body
            var res = await RestManager.Instance.ExecuteRest("getKey", stringc);
            //Null if the api is down or if there is an error on the api's side, manager reports this to another api call that saves
            //the api response/ stacktrace, offline is when the user doesnt have connection.
            if (res != null && res != "offline")
            {
                //So here Res is Not NULL and Not Offline, so the null reference cant happen here.
                var resm = JsonConvert.DeserializeObject<RegistrationKey>(res);
                //Another check JIC also references crossfirebase but would be weird if this is the case.
                if (resm.RegToken == "" || resm.RegToken != CrossFirebasePushNotification.Current.Token)
                {
                    //More of the same, create a request to send to the api
                    var request = new RegistrationUpdate()
                    {
                        RegToken = CrossFirebasePushNotification.Current.Token,
                        SerialKey = Helpers.Settings.License.Replace("/", "").Replace("\\", "").Replace('"', ' ').Trim()
                    };
                    try
                    {
                        //Stuck this in a try catch to see if this part was the cause, since it would just continue on and not crash.
                        //But the crash still happens so this part isnt the cause
                        var stringContent = new StringContent(JsonConvert.SerializeObject(request), Encoding.UTF8, "application/json");
                        await RestManager.Instance.ExecuteRest("SetPushtoken", stringContent);
                    }
                    catch
                    {

                    }

                }
            }
}