Vodacom

On 21/03/2015 I took my daughter's phone to their branch. She received 2 sms messages that week to say that they had received the phone. Today 13/07/2015 we went into another branch of Vodacom to ask them if they could find out what the hold up was. Only to discover that the phone had been returned to their branch on 25/03/2015!! They told us that it was water damage which is complete ******* as the phone was working fine just not charging. When we put in a fully charged battery from another phone it worked without a hitch. Water damage was never even considered by ourselves or them when we took it into them on 21/03/2015. How do I know after 3 and a half months that the damage was not their fault. I think that this is just a default response so that they don't have to honour the warranty. Of course they promised to phone me back today but as of close of business today nobody had called. My questions to them are 1) Why did nobody call me to inform me that the phone had been returned? 2) How do I know that it was not damage caused by them? 3) Why was I not given the opportunity to ask them to repair the phone in March?