What just happened during my ride on SMRT

So i was riding a C151A towards Joo Koon, the train was arriving at Raffles Place ( take note that the STARIS and PIS is off from Pasir Ris bc i started my journey at Pasir Ris ) then the PIS suddenly turned on, saying we are heading to Marina Bay then it changed to Tampines then after it said track crossing ahead, im so confused. ( some words missing bc i screenshot from a video i made of it and i couldnt upload the video to Reddit )