Maybe google the token that you're trying to sell, or look it up in a website such as Coinmarketcap,
https://coinmarketcap.com/If it's not listed on there (CMC), you might be wasting your time, since it is most likely a shitcoin that you're advertising.
it's not always a scam, it's cause cmc requires a consistent daily volume to list a coin.
many new coins are listed first on coinlib.io. blockfolio is fast to add them too.