Lab 10.4 - no lab environment loaded on page

Hi,
Is there any issue with Lab 10.4 web page?
I can see the PDF with lab instructions, but there is only please wait page showing below,

then said “Sorry!
There was a problem preparing your lab environment: Timeout when launching stack.”.
Reloading or re-accessing the course does not help.

It looks as though something was misconfigured in on of the labs. Please reset your lab environment by clicking on the Reset button in the lower right corner of the lab environment.

It become the blank screen now, I can see nothing but mouse point. Then show me the messages.

Well, if I click the reset button, then all LAB configurations from 1 to 10.3 will all reset to the very beginning as instruction said, right?

Correct

Oooops, it is really a bad news, I almost done all the labs.
The lab connection status is very bad, the screen stuck all the time, you have to refresh the browser again and again to get action, it is really a challenge to complete all labs, please improve it.

I will check with our lab vendor to see if there is an issue on their end.