Vodacom arrogance-locking independent phones to their network only.

Profile is a company that has an Internet application as well as a Mobile app accessing the data from the Cloud. The App has reverse billing capability and thus I need a Vodacom, MTN, Cell C and Telkom sim card to test the reverse billing app on all teh Servcie Providers. I purchased two Service Provider independent Mobicel phones to test the reverse data facility on. I inserted the Vodacom card into one of the phones and now the phone has been ‘locked’ into Vodacom only. Who gives Vodacom the right to lock my phone into them as the only service provider. It is arrogance beyond belief. I now wish to insert one of the other service provider sim cards into the phone but the phone won’t recognize it. I DELIBERATELY bought Service Provider independent phones. I am so angry I could spit and many expletives that are not appropriate on this forum. I want Vodacom to unlock my phone back to the state I bought it in. Arrogance is putting it politely.