Not able to create phone call activity in Dynamics crm 365

Hi All,

My query is I need to create one phone call eclation activity

the scenario is when the case is created one phone call activity is created if the user did not respond to this phone call within 10 mins then another phone call activity is created.

I try to create this activity using out of the box workflow , but it's not working as per the requirement, not able to set the duration,

can someone explain to me how to do this, or what is the best approach to achieve this requirement?

Thanks & Regards,

Jyotsna