Hey,
after 2 days that i didn't used the mavic, yesterday it did an update before flight.
and then i did compass calibration and, imu calibration.
and now it has a problam flying down ! :-(
When i push the stick down or when i press the land or return home, it's  flying down very very very slow. About 1m for 3 sec.
(All the oter flying direction working perfect.)
I've been trying changing propellers didnt fixed it.
Help please!

What firmware version is your Mavic and RC on?

Make sure the RC and drone both are up to date, calibrate the RC, then try it again , if it is still the same, please sync your flight records , then provide me your DJI Account email and the date of this occurred, so
I can check it.

yesterday it did an update before flight. and then i did compass calibration and, imu calibration.

Were you prompted to do the calibrations? When everything is working correctly you generally should avoid doing calibrations unless prompted to by the app.

Diana's control stick calibration suggestion is worth trying, but if that doesn't work you might try downgrading the firmware since it appears there might be a connection to which version you're using. And if that still doesn't fix the problem you may want to retrieve a DAT file from a flight where this occurred, upload it to DropBox, and post a link to it here, after which someone will look at it and see if the problem can be identified. The DAT file is stored on your Mavic and the instructions for retrieving it are here.