Telkom- Very Disappointing

I bought a brand new Iphone 12 from Telkom, the loud speaker does not work at all, the phone came like this, but I only realized it a few weeks after purchase, so nobody can hear me when talking through whats app or on loud speaker, Any way I contact telkom and they say I need to book it in for repair, NOW my question is how must I go without a phone for how long because we all know that Telkom is not very fast, how come you can't give me a replacement phone while mine is in for repairs, Telkom does not even try to accommodate me, I am seriously not going to carry on with my contract with them.