Vodacom network: Not allowing my 2 vodacom sim cards in my duel sim phone

I have 2 phones and a modem (usb ****le) on a contract with VODACOM. I'm not using my modem anymore and wanted to put the sim card in my dual sim phone. Huawei P30. Only one sim slot is currently occupied..

I know for a FACT that the phone is capable of handling 2 sim cards. I also know that TELKOM customers can put a TELKOM and VODACOM sim card in the same phone.

Just imagine my surprise when I went to a Vodacom dealer and was informed that the phone is capable of handling 2 sim cards but (After I've done my sim swap, for a nano sim) that the VODACOM network doesn't.