I use the Viber app and have a subscription for Unlimited worldwide calls. Its been working fine but now i cant call mobile phone numbers in other countries,the prefix etc is there..what could it be thats blocking the app from making the calls?

Maybe Viber knows

Is the subscription still active?

Has your phone got data?

Have you tried on a different internet network?

Is your WiFi fast enough?

Have you updated the Viber app?

Have you restarted your device? (PC / Phone)

Have you restarted your router?