Network issues.

I have been struggling with network issues since last week. My text messages are not going out nor coming in. Every time I receive a message saying ( not network chosen) I don't know what this means. My banking is suffering because I don't get notifications where I get money in or out of my bank account. This could lead to ********** activities happening in my account. All I am able to work with is gmail and what's up. Other apps are not working especially the SMS functionality. I gave enough data and also use Fibre so what is the problem will Cellc. Sometime last they advised me that they are migrating me to Vodacom, has that happened I don't know. All I know is that I am unable to use most of my services. Can somebody tell me what the issue is and fix it? I am still paying my monthly subscription via debit order so what's the deal ????????? Please fix this issue as soon as possible