How can I communicate between Service app (background without UI) and normal native app (with ui)?

I tried with message port.

I was able send message to service app but the service app didnt recieve the message.

Then I tried to send message to ui app  when starting the service app using a timer 1 sec interval. but after 10-15sec the service app stoped sending messages.

At starting of the service app it able to send msg and recive msg, same for ui app too.

but after 10-15 secs the service app neither recive msg nor send message.

Is there any other technique to communicate with service app and ui app?

Or did I missed something, thats why service app stoped responding after sometimes?

Thanks in advance.