Gboard on Samsung Galaxy On5 - CACHE!?

[Android Central Question]

Hey all. New to your site but have a question about Gboard. I've got a Samsung Galaxy On5 with 8 GB onboard and a 16 GB SD card. Was cleaning out my cache to try and save space, darn thing is always telling me it doesn't have enough space. and looked at it. I says I have 77.60 GB, that's right Gigabytes not Mega, in cache! Ok looked through my apps and found that Gboard was the one that had 77.60 GB of cache. How can this be possible? There's only a total of 24 GB memory for the the whole phone, onboard mem and SD card. Is it using the cloud and putting data there to create the cache as well as using my memory on the phone or is there something wrong with it? I've never seen anything like it. I tried to clear the cache for Gboard but it won't let me. So my question is what do I do?