It is a Hong Kong based exchange that started in 2018. Btcdo launches a platform with a few features that may not be very popular in the crypto market. The liquidity and volume were small from the beginning, and their official application had a lot of errors that needed to be updated frequently.
Although the Btcdo platform was moving forward with a decent amount of community, they moved on to a system upgrade after finishing handling charge destruction last year,
Some days the platform is in read-only mode but since then the platform has not come online and the team has not made any announcement in this regard.
From my personal experience I think Btcdo Exchange will not come back online so I think it is better not to expect anything from Btcdo Exchange.