My daughter is 1 year old, and i am working mother. i have joined office 15 days ago. the day i have started going to office, i saw change in behavior of my daughter. she is not playing, not laughing, not doing any activities?

She may be experiencing separation anxiety. Find ways to visit during your work day, by phone or by video. Establish a routine that allows you to spend time together. Read together before bedtime. If the behavior doesn't improve, please see your Pediatrician. Watch for signs of fever and illness.

This is quite common and you could use some routines to ease the anxiety . Create specific rituals like giving her three hugs or a rhyme she loves to hear , before you leave, but make it short . Also you could leave her something of yours , that will tell her you will be back .You could also get her used to your being away for a short time and then returning .