Login issue - shell request failed on channel 0. #cant login to labs

can I get some help on this error to get it fixed?
I can’t log into the labs as it shows the following error. I tried both ssh and website.

Issue is resolved, try to login now. There are many sessions opened which caused the issue, close the sessions using ctrl d once your practice is done.

Thanks hemanth.
I wasn’t aware of the session. Will definitely do it fom now on.