You aren't actually banned, it's an IP conflict. Follow the instructions below to solve it
Arvizx
Method#1
Turn off your Wi-Fi router, wait 5/10 minutes, turn it back
ON, only works for Dynamic routers.
Method#2
#1. While on desktop, press
WIN + R, something like
THIS should pop up.
#2. Type
CMD in the typing field given there,
EXAMPLE. A window like
THIS will pop up.
#3. Type
ipconfig /release and press enter, wait for the command to get processed,
EXAMPLE.
#4. Type
ipconfig /renew and press enter, now your IP will be renewed.
#5. Close everything, and restart Minecraft.
If these two methods didn't work for you, you may join the
discord server and go to #assistance_chat. Ask a staff to create an IP-Conflict ticket for you.