If you do not have a driver for the corresponding network card, then this is due to an unstable Internet connection. We need to know the driver version.
first we find out the name of the network interface:
# apt install net-tools
# ifconfig
find out the driver name:
# apt install ethtool
# ethtool -i eth0` # specify the name of your network interface
there will be something like:
driver: via-rhine
version: 1.5.1
To find out which driver is installed and detailed information about the card in the configuration section:
# apt install lshw
# lshw -class network
configuration: autonegotiation=on broadcast=yes driver=via-rhine
driverversion=1.5.1
then look for the driver using apt:
# apt search name-your-driver