First of all, thank you for the samsung support team in Philippines 😊😊😊😊. I can now enjoy the themes i downloaded.
For it to work in your message and calls app, try to clear cache from galaxy store or galaxy themes, whichever you used then reset your apps, and make sure to disable Dark/Night mode of your phone. 😉. Enjoy your THEMMMEESSS🌈🌈🌈🌈