Possibly your CA certificate is malformed or invalid.
The file size looks too large for a usual CA certificate. Please try to open it in a text editor and check if it looks like this
-----BEGIN CERTIFICATE-----
<several lines of characters>
-----END CERTIFICATE-----
or try to verify it with openssl
openssl verify -CAfile /etc/openvpn/client/ca.crt /etc/openvpn/client/ca.crt
It is possible that a driver in the new kernel is broken to some extend. The situation with those wireless chips is awful but I suspect you are running into a problem, that network-manager does not let you use your adaptor. You need to add wlx0013ef6c46e3 to ignored interfaces. I am also not sure you need a special realtek-hostapd for this adaptor. Try both methods.
echo "[keyfile]" > /etc/NetworkManager/conf.d/10-ignore-interfaces.conf
echo "unmanaged-devices=interface-name:wlx0013ef6c46e3" >> /etc/NetworkManager/conf.d/10-ignore-interfaces.conf
service network-manager restart
An armbian-config method should take care of this, but it also has some rough edges when setting AP.
In any case, I recommend you an upgrade to something like this. A class better than 8192.
