why do i keep losing my dial up conection?

Answer 1

There may be several reasons.
Some ISPs automatically disconnect after so much inactivity or just after some amount of time in general.
Your computer may disconnect afer it detects the Internet is not being used.
Your phone line may be bad.

It's best to contact your ISP for diagnoses.

Answer 2

Hard to answer this with no details. My first thought is to make sure call waiting is turned off.