suspending account without notice

My account was always with Nashua mobile until the change over to VODACOM. I've always made sure that my bill is paid every month by the 25th no debit order as Nashua would debit my account twice so they agreed that I pay eft. The problem happened when I paid my account in December into the Nashua mobile account as I never received any bank details or notice from Vodacom - they disconnected me this month because they said I never paid my account! I paid what was owed for January straight away while vodacom was on the line with me I then explained that I paid my December account into the Nashua mobile account and I cannot get hold of anyone at Nashua to refund me! Vodacom then gave me the email address and number to contact at Nashua still I cannot get hold of anyone - I've phoned and emailed and no response. Vodacom understood my situation at the time and activated my account again and said when I get refunded I can pay them! I have not yet been refunded therefore I cannot pay vodacom! Vodacom have deactivated my account again without any notice! I need to know how else to handle this! I've done everything.