Most people using vodacom network can't get throug

I have been calling the telkom mobile call centre to resolve the issue mentioned below with no success at all. The issue is most people especially those using vodacom they cannot reach me when the network changes or roaming on MTN network it keeps on saying on canceled their calls by prompting call ended while they try to call me. I have tested these with other people that are using telkom mobile SIM cards same thing happens. I phoned the call centre they gave me codes to reset my phone and the problem is still not solved. This is a very bad experience and I won't renew my contract with telkom mobile because there is no use of having a phone and people can't phone me.