Question [Q] Samsung keyboard input problem

When want to write messages & on samsung keyboard, swipe the space bar to change language keyboard input, it won't change the
language. As on samsung keyboard settings, input languages, as there is 2 languages on it.
However on keyboards and input methods, the samsung keyboard tick is grayed out.
There is just only Samsung Keyboard & Google voice typing.
When I did factory reset, it did work. But later when adding some apps,
later it won't work of changing languages..
What's the problem?