To generate a new token go to https://jwt.io/ and copy the current token.
Generate a new secret that's 32 or more characters.
A simple command on Ubuntu to generate a random string < /dev/urandom tr -dc A-Za-z0-9 | head -c32.
Paste the new secret in the secret section on jwt.
Remember to change the current JWT_SECRET in the docker-compose file and update token.txt