No way to resolve a roaming issue - stranded overseas with no way to contact MTN

I am currently in Spain and have my call roaming is not working, it has now been 4 days without resolution. I can't make or receive calls, I get no notification of missed calls and no messages. There is no way of contacting a MTN Call center agent as neither 135, +2783 135 nor +***0 or +***6 are contactable. Your customer care email goes unanswered. What do I have to do to get my roaming and voice messages working. Please send a contact number and email address that can be used to resolve this issue URGENTLY!!!!