Harry Potter Mandela?

In the Prisoner of Azkaban movie, who else remembers Snape saying "Well well, Lupin.. Out for a stroll in the moonlight are we?" That's how I have remembered and recited it for about 20 years! WELL.. I was watching it on HBO max the other day and Snape now says "Out for a WALK in the moonlight" Which is wrong, right?! I instantly put on the dvd I've had since it came out to prove it, and it too says Walk not Stroll............ This isn't right, right??