Why can't I make or receive WhatsApp calls?

[Ella1604]

Hello please I need help.
I use Samsung j5 and since we moved in our new school(boarding school) I haven't been able to use WhatsApp for calls.. I check online and was told it was because of the high number of users.. But everybody else has access to that except me.. And not only whatsapp calls also imo tango and all those apps except for facebook messenger.. please help me am getting frustrated

 

[B. Diddy]

Welcome to Android Central! Are you trying to access those apps using wi-fi or mobile data?