If you post a code snippet, ALWAYS USE CODE TAGS:
How to use code tags: Using code tags properly
The answer is always the same for NullRef… ALWAYS!
How to fix a NullReferenceException error
https://forum.unity.com/threads/how-to-fix-a-nullreferenceexception-error.1230297/
Three steps to success:
- Identify what is null ← any other action taken before this step is WASTED TIME
- Identify why it is null
- Fix that