Be extremely cautious if you receive a text message asking for a code related to Grindr. According to the Grindr Help Center :

Alex was intrigued but also a bit skeptical. He had heard stories about scams on dating apps, and the offer seemed too good to be true. But there was something about NYCexplorer that made him feel like he could trust him.

These are legitimate alphanumeric codes released by Grindr or their partners (usually during Pride month, holidays, or for new users).