Hello! I see you're having trouble sending and receiving SMS messages while roaming in Russia, and that it’s preventing you from authorizing your app. Let’s try to get this sorted out together.

First, just to confirm a few things:

1. Is your International Roaming service activated on your Turkcell line?
2. Have you set your network selection mode on your phone to "Automatic"?
3. Is your phone showing any signal bars or connected to a local Russian network?
4. Have you checked if your phone can send/receive regular calls while in Russia?
5. Is Airplane mode turned off?

Usually, SMS issues in roaming can happen if the International Roaming setting is off or if the phone is manually locked to a network that doesn’t fully support SMS for your Turkcell SIM.

Here’s a step-by-step to try:

1. Enable International Roaming
Go to your phone's Settings > Mobile Network or Connections > Roaming, and make sure International Roaming is enabled.

2. Automatic Network Selection
In Settings > Mobile Networks > Network Operators, choose “Automatic” so your phone connects to the best available network.

3. Restart Your Phone
Sometimes a simple restart helps re-establish connection with the roaming network.

4. Check SMS Center Number
This is a little advanced: On SMS settings, ensure the SMSC (SMS Service Center) number is correctly set for Turkcell. If you need help accessing this, I can guide you through.

5. Try Using Wi-Fi for App Authorization
If SMS still don't work, some apps allow authorization via internet (Wi-Fi or mobile data). Is mobile data working for you?

If after these steps SMS still don't arrive or go out and you cannot log in, there might be an issue with Turkcell’s roaming agreements or restrictions specific to Russia. In that case, contacting Turkcell support or the roaming partner might help.

Please let me know what you've tried so far and any other symptoms you notice, so I can assist further!