So you may try to apply 2 solutions:

1) Go to Studio->Developer App and find on the first page the option "Use GD library for image processing ". Disable it then the system will be switched to use the Imagemagick - sometimes it allows to keep the GIF animation after the resize.

2) If the previous step doesn't have effect execute the following query in your UNA database (backup it first):

DELETE FROM `sys_transcoder_filters` WHERE `transcoder_object` = 'bx_albums_big' LIMIT 1;

It will remove the resize part. Then go to Studio->Dashboard->Caches area and clear all cache.