Bancor, a “DEX,” is following the lead of many others and geoblocking the US. Bancor will restrict all US users from trading.
Like most exchanges doing this, they say you can still use the service as a wallet, you just can use it to trade.
You can learn more from their official post titled “US Service Restriction.”
Here is an excerpt from the article with the information you need to know:
Beginning July 8, 2019 (9:00 AM EST) US citizens, domiciliaries or users from US IPs will no longer be able to use Bancor’s web application, https://www.bancor.network, to convert tokens.
If you have a Bancor Wallet, you will still be able to log-in, hold tokens, and transfer tokens from the United States. Only the convert functionality will be disabled. This decision has been made in light of increased regulatory uncertainty; at this time, we believe this is the most judicious decision for all the members of our ecosystem. This will enable the Bancor community and ecosystem to innovate faster and with greater clarity.