Hello Ugyen! It’s been a while, hope you’re well and healthy. I’m glad to see this unit back in action!
The PAN010 unit (UArizona) encountered this problem last November. The likely issue is there’s a problem with the IERS source website. This has been a documented case with Astropy. I think Wilfred (@wtgee) pointed to a website mirror for us to fix it. We got this update by downloading the docker container and installing
POCS through there. I’ll leave it to Wilfred to guide you through on this, since he’s probably put in additional updates since we encountered this.
This is also potentially unrelated, but one problem could be your internet security connection. We had no problem with the IERS tables when we were testing indoors using the university’s wifi connection. However, our outdoor testing site (the roof) was not internet ready and when we tried using a cellphone data plan for internet connection, it gave us this error. We eventually got a secure internet connection on the roof. Even if it doesn’t work, it doesn’t hurt to try connecting your unit through a hard wire connection.