TrueCaller shows switched off number working

[manchup]

My friend using dual sim mob. with true caller installed shows the number in use but on calling the same no. it says "mob. is switched off".Tried calling from different no's with same result.And checked on various mobiles with truecaller, I can see the number is in use.
can anyone help with this.
Thx in advance

 

[manchup]

Is there any1 who can help me with this? I'm developing a similar app