shared line keep ringing in another phone when a user hangs the phone

[yasiromer11]

i have a problem with a shared line

a line is shared on Phone A and Phone B, when the line rings and user phone A answers the phone and hang up the number ring on phone B

how can I stop the number from ringing phone B when user phone A ended the call.

thank you 

[Chris Deren]

Sounds odd, what system is this on, what version, what phone models and firmware version?

Does the phone B continues to ring after phone A answers the call, or does it start ringing after phone B hangs up?