Solution

List your shells

cat /etc/shells

Find your current shell

echo $SHELL

Change your default shell

chsh -s /path/to/shell

Examples:

chsh -s /bin/sh
chsh -s /bin/bash
chsh -s /bin/zsh

References

• https://www.cyberciti.biz/faq/change-my-default-shell-in-linux-using-chsh/