A little hard to say with the details provided but here are some things that could cause an issue :
- Tokens are in email draft and draft is not approved
- No value in the fields you are trying to use as tokens (and the default value is removed)
- Something in Marketo is setting field values which are used as tokens and the email is being sent before these actions run
If you can post some screenshots of the email / setup, provide the example tokens you are trying to use and check if the email is approved, we can try to figure out what's going awry.
hope it helps!