No connections to mssql in docker compose

I have two containers that run via docker-compose, my docker-compose looks like this
version: "3.7"

services: 
    mssql:
        build: ./Db
        ports:
            - 1433:1433

    planning-poker:
        build: .
        restart: always
        env_file:
            - env.list
        ports:
            - 80:8080
        depends_on:
            - mssql

Dockerfile go-app:

FROM golang:latest

RUN apt-get -y update && \
		apt-get install -y net-tools && \
		apt-get install -y iputils-ping && \
		apt-get install -y telnet

ADD . /go/src/planning-poker
WORKDIR /go/src/planning-poker

RUN go build -o main .
ENTRYPOINT ["./main"]

Dockerfile mssql:

FROM mcr.microsoft.com/mssql/server

ENV ACCEPT_EULA=Y
ENV MSSQL_SA_PASSWORD=Yukon_900

EXPOSE 1433

USER root

RUN mkdir -p /usr/src/app
WORKDIR /usr/src/app

COPY . /usr/src/app

RUN chmod +x ./run-initialization.sh

USER mssql

CMD /bin/bash ./entrypoint.sh

I am using database initialization scripts:

for i in {1..50};
do
    /opt/mssql-tools/bin/sqlcmd -S localhost -U sa -P Yukon_900 -d master -i SQL_PlanningPoker.sql
    if [ $? -eq 0 ]
    then
        echo "SQL_PlanningPoker.sql completed"
        break
    else
        echo "not ready yet..."
        sleep 1
    fi
done

So is my entrypoint:

./run-initialization.sh & /opt/mssql/bin/sqlservr

The problem is that I can’t connect to mssql from the container with the golang application in any way, the connection passes from the host, I tried to connect via telnet to mssql from the go-app container on localhost 1433, 127.0.0.1 1433, 0.0.0.0 1433 but always I get an error that the connection is either reset or telnet cannot resolve the addresses.
MyProject: https://github.com/philomela/PlanningPoker/tree/master - master branch.
What am I doing wrong? thank you in advance!

try adding network and kepp all services run in same network

networks:
    my-network:
services: 
mssql:
    build: ./Db
    ports:
        - 1433:1433
    networks:
       - my-network

planning-poker:
    build: .
    restart: always
    env_file:
        - env.list
    ports:
        - 80:8080
    depends_on:
        - mssql
    networks:
       - my-network

Also there is a possibility to check service is healthy with some heath check rather than just depends_on because docker may be up but SQL server would take some time to be up and running

https://docs.docker.com/engine/reference/builder/#healthcheck

The issue is resolved, I suffered for several days, but did not pay attention to port forwarding in my application, now everything is working stably!