airtime missing

I have recharged with R55 on 1st dec 2017 and I was about to recharge my data again and fob has some issues and I couldn't login and my data completely finished. and I turned off 3G data off and I see my airtime to 45 instead of R60.something.haveing previous 6 rands total I have been using Vodacom fro more than 8 years and now its getting worst with their data usages terms and conditions. and I have once noticed missing airtime as well as I have checked it only for once I have made a call twice and my calling plan is .79c per min and they are charged more that that for two of my calls, so guys please be aware of your airtime if you have Vodacom. really not happy with this service provider, can you please suggest any other service provider other than cell c.