Reading ERA-5 TCWV data

Hello, I hope I am posting in the right place. I downloaded the ERA-5 TCWV data for every month and every hour from 2010-2021 using R.
But I ran into two problems. The first is the latitude and longitude problem. I entered 41.81 degrees East and 40.23 degrees North (west and south are fine). But when I checked it, it shows 41.62 degrees for East and 40.07 degrees for North. Why might this be caused?
my second problem is julian days. When I want to export the file with Panoply, the date is transferred as julian days. I haven't been able to translate julian days with R either. I would be very grateful if someone could help me with this. These data are very important to me. Thank you from now.