Why can't i download Whatsapp on my child's Microsoft Lumia 640?

[ztania97]

Can't download whatsapp on my child's Microsoft Lumia 640

When trying to download asking for a family set up.
I went to my Microsoft account, set up a family, added my child.
He accepted the invitation.
Already had xbox life, with billing information (have annual subscriptions for xbox live).
Still can't download whatsapp.
Increased my child's age to 19 - all the same.

Please help. Thank you

Updated for Libra89: yes, he does have a sim (provider - talkmobile). it's a new phone/sim/contract, just bought it last week.

 

[boltman2013]

Re: Can't download whatsapp on my child's Microsoft Lumia 640

Turn off the set automatic date and set the date and time correctly......and try again.....if u get error again better soft reset (Power+VolDown until off).....

Settings> Date and Time

 

[ztania97]

Re: Can't download whatsapp on my child's Microsoft Lumia 640

Thank you for your help! It worked eventually! Phew.....