Debian live boot problem

[Dmitry Unruh]

Hello!
The debian-live-9.0.1-amd64-kde+nonfree.iso does not starts up in live mode.
It shows login screen again and again.
After typing password (live) it shows the desktop for a few seconds
and reset again in the login screen.
No errors print.
P.S.: System installs from the image correctly.
What should I do to fix the incorrect behavior?