animation from blender is being applied to all objects when exporting to unity


i’m adding some button and tray animation to this grill machine. when creating the animation, i selected the object and inserted keyframes. it all appeared to go well in blender (animations are being applied only to desired objects)… however, when importing to unity, the animations where applied to all my different objects - even the ones which i never attached an animation to. am i doing something wrong when creating the animation? or exporting?

please see attached images for a better explanation.

thank you!

ps: since i’m animating buttons, i didn’t add any bone/armature. is that necessary? maybe that’s what’s causing the weird behaviour?