Cannot open MiKTeX, error “File is empty”. Cannot uninstall

I am using KDE neon. After I installed MiKTeX, I updated everything from it, downloaded the "standard package" and then tried to install TeXStudio... a message appeared "installation failed". But TeXStudio is fine. I can run it. I go to MiKTeX Console... and suddenly I am unable to enter, getting this message: Panic ensues. MiKTeX actually says in their documentation that entering the console is needed to first restore initial status to fully uninstall it. But I can't. Trying

-shell
sudo apt-get purge miktex

does nothing good. It says that there is an empty file, the same thing as when you try to open the console: > miktexsetup: File is empty. > path="/home/MYUSERNAME/.miktex/texmfs/data/miktex/data/le/90a0591fc444a4d943d26e2f84799e00.fndb-5" ---------- When executing

-shell
sudo dpkg --remove --force-remove-reinstreq miktex

I get this:

(Reading database ... 174113 files and directories currently installed.)
Removing miktex (2.9.7300-bionic1) ...
miktexsetup: File is empty.
miktexsetup: Data: path="/home/MYUSERNAME/.miktex/texmfs/data/miktex/data/le/90a0591fc444a4d943d26e2f84799e00.fndb-5"
dpkg: error processing package miktex (--remove):
 installed miktex package pre-removal script subprocess returned error exit status 1
Errors were encountered while processing:
 miktex

What am I supposed to do? MiKTeX Console still appears as if it is still a program.