I have a problem while building docker. Error is following:

     => => transferring dockerfile: 327B                                       0.0s
     => [internal] load .dockerignore                                          0.0s
 => => transferring context: 2B                                            0.0s
failed to solve with frontend dockerfile.v0: failed to create LLB definition: failed to parse stage name "postgres:": invalid reference format
ERROR: Service 'postgres' failed to build : Build failed

I tried to find what was the problem, but still stuck with this, so I kindly ask for your help. This is the Docker file:

FROM postgres:${POSTGRES_VERSION}

ARG TZ=UTC
ENV TZ ${TZ}
RUN ln -snf /usr/share/zoneinfo/$TZ /etc/localtime && echo $TZ > /etc/timezone && chown -R postgres:root /var/lib/postgresql

#COPY my.cnf /etc/postgresql/conf.d/my.cnf

CMD ["postgres"]

EXPOSE 5432

Not sure what can be the problem here, but I'm getting an error mentioned previously. Thank you in advance for your help.

UPDATE: It was an error due to problems with reading version of postgres, as @Makariy mentioned in comment.