If you're referring to DJI Flysafe,
Red zones are DJI categorized restricted which needs custom unlock through the Flysafe website. These could be for military, jails, runways of high traffic airports, immediate surrounding area around a major airport.
Blue zones are DJI categorized authorization zones which can be unlocked in the field if you have internet and text there, otherwise get a self-unlock from Flysafe site. These would be similar to red zones but not as risky.
You can easily see the flysafe map from staring page of Fly app, upper left of screen. You might need to enable showing zones.
Red zones are DJI categorized restricted which needs custom unlock through the Flysafe website. These could be for military, jails, runways of high traffic airports, immediate surrounding area around a major airport.
Blue zones are DJI categorized authorization zones which can be unlocked in the field if you have internet and text there, otherwise get a self-unlock from Flysafe site. These would be similar to red zones but not as risky.
You can easily see the flysafe map from staring page of Fly app, upper left of screen. You might need to enable showing zones.