The passed Environment Variables is not working well in compose file.

I tried to set PMA_HOST,PMA_USER,PMA_PASSWORD but has no effect, though when I tried to echo these variables from the bash inside the container, it worked well

here the compose snippet

environment:
- PMA_ARBITRARY=1
- MYSQL_ROOT_PASSWORD=
- PMA_HOST=172.16.238.5
- PMA_USER=root
- PMA_PASSWORD=