Why am I having trouble sending GIFs?

[Mowerheimen]

Not too long ago I switched from an iPhone 4s to the Samsung Galaxy S5 Active. With my iPhone, I never had any trouble sending GIFs of any size to other iPhone or Android users. Since the switch, I've downloaded Textra, and even gone in and upped the setting to let me send larger GIFs, but they just won't send at all, even on the smaller end (for instance, I attempted to send a 2mb gif that kept failing). It just keeps telling me the message failed to send. I don't want to use Google Hangouts to send GIFs, but I don't mind trying other messenger apps.