International dialing

I have had an account with MTN for over 20 yrs***). I have always had international roaming and dialing. The cost of this was always debited to my account, If I had spare time in my bundle it was taken out of that else added to my account. This has now changed and I have to download the MTN app and but airtime. Why has this changed and is it correct or can it still be done on my account?