I can't check my voicemail on my Vodafone Tab prime 7 Android 6.0
Cause 4 of 4: You're trying to check your voicemail when abroad
The default voicemail number can only be used if you're calling form your home network.
Solution: Call 172 to check your voicemail. If you can't call 172, call +353 (prefix) 5 (your phone number) instead to check your voice messages when abroad.