mobile

I have a Note 10.1 with a 32gb sd card. I put a bunch of mp4 movies on the card and can play them without any problems on my note 10.1. I started running low on space so I got a 64gb sd card. I copied some movies to the card and figured everything would play just like with the 32gb card. However, the movies won't play. They are on the card, the titles show up on my list, but the length of the movie shows as 00:00:00. I know the data is on the card Beca use when I look at what is taking up space on the memory card, the movies are a big chunk of it. Can anyone tell me how I can get them to play? I don't get what the difference is between playing from the 32gb card and the 64gb card.

Thanks, GL