Thank you for reaching out. Can I please have your full model number, baseband version, and the software version for your Samsung Keyboard?
Give this link a try: https://us.community.samsung.com/t5/Galaxy-S10/No-GIFS-or-stickers/td-p/1189209/page/3
Please see the step provided by @David9193
Mine said the same thing and I just fixed it just by going to my messages and clicking on any message just to bring up the keyboard and I clicked on gif and says go to the galaxy store and it's going to say keyboard content center and click install and there you have it your gifs are all back