Fix ESP32 LoRaWAN Code for TTN

I'm experiencing issues with my ESP32 code for LoRaWAN OTAA. Specifically, my device isn't able to join The Things Network (TTN). I've verified that my device credentials and configuration are correct, so I need an expert to help troubleshoot and resolve the issue.

Ideal Skills and Experience:
- Proficiency in ESP32 programming
- Experience with LoRaWAN and TTN
- Strong problem-solving skills
- Ability to troubleshoot network connection issues
- Knowledge of SX1276 module

Please reach out if you can assist with this issue.