Due to our regulatory strategy, which you can read more about in our Medium post, we are unable to add every token. There are thousands of ERC20 tokens and each one added to Radar Relay involves a review process. The most likely answer is that either the token failed our Howey Test framework, indicating it is likely to be a security, or that we have been unable to get in contact with the token issuer.

If you would like to see a new token on Radar, see our article "How do I get a token added to Radar?