FreeMe 20 gig complaint

Good day I would like to lodge a formal complaint about the package I am on, FreeMe 20gig When it comes to data, if my allocation for music, video or WhatsApp is depleted, it takes from my ‘all networks data’, which is fine. But when it comes to ‘voice’, if my Telkom minutes (300) are depleted, I cannot make any calls anymore to Telkom numbers whereby I have 1500 off-net voice. This is not a practical SOP because as a customer, the reason I am on such a high package is because I call a lot and require a lot of data and especially make a lot of specifically Telkom calls. Can this please be looked at, as it is a serious inconvenience