For you to decide..

Throughout the entire day, USD/BTC was hovering ~$16.3k

@6pm USD/BTC hit $17k, and has maintained a smooth upward graph

Luno on the other hand, still reflects a downward graph which does not match the real-time value (at this point you are still at a loss, while the whole world is going up).

Not sure if there are underlying reasons to why this is happening but trust for their service is definitely LOW on my end!