if you see this error when opening a lab/assignment:
“We were unable to retrieve a launch URL. Please make sure you are logged in to Coursera, and have access to this lab.”
make sure you have a valid subscription
try if you can open it from (a) incognito mode of your browser / (b) another browser / (c) another device. If you can, you may clear the cache of the browser in question and try again.
if none of the above works, you need to contact Coursera which manages your access and your account. Click this link to start.
Quoted from coursera:
You’ll only be able to access your Coursera Lab assignments and Jupyter Notebooks if you have a paid Coursera membership. If your subscription ends, you’ll be put into audit mode and won’t be able to access them