No follow up's

I bought the new P40 in November last year and the sim that comes with it is still not working,I have been 3 times to there store in Meyerton to ask regarding this and if they can have it sorted out for me and they said yes they will log a ticket and someone will be in touch soon....19 days later still awaiting there call. I then went and added an additional contract with them and I have to phone them the whole time to find out whats going on. I am at the point of cancelling both my contracts with them!!!!!