While I cannot advise specific technologies since I don’t know what languages, databases, or environments you’re running in - general guidance is that you need to encrypt the token in your code when you get it, then you can store it in a database. Decrypt it after you retrieve it. The encryption/decryption should be happening on your server, this isn’t simple database encryption where its encrypting data on disk but decrypting the data when you query it.
The main consideration is that you don’t have the ability to access the keys to decrypt it, nor do any users. Only the server has the ability to access the keys and use them (and not stored in code!).
If you were to query the database what you’d get back is encrypted data, and no way for you to decrypt it - even if you tried.
Make sure you don’t log tokens anywhere of course!