Forgot this movie title?

In this kids movie were the 9 reindeer (people in reindeer costumes
with the fur and antlers and so forth) and each wore a different color
sweater with their name on it. EX. red sweater blitzen and green
sweater Donner....etc They were up north with snow on the ground and i
remember one deer being sad and it was also a musical kinda because he
sang a sad song. If you know the title, please tell me....i just cant
remember