Several calls and hang-ups

I received a call from this #.  I was busy and didn't answer.  I called back and got the disconnected message also. That was on 4/15.  I got another call a couple of days later but did not answer it either.

i got a call from this number that i missed when i called it back and it said the number had been disconnected.

they said it was tim from federal home something and then i got disconnected, i called back and it says the numbers been disconnected or not in service.