It’s really best not to be running an OS beyond end-of-life. I recommend that you upgrade to 22.04 in a couple of weeks and then stay on that for the next 2 to 5 years. 
It’s really best not to be running an OS beyond end-of-life. I recommend that you upgrade to 22.04 in a couple of weeks and then stay on that for the next 2 to 5 years.