The keyboard not working until you clear the cache sounds kind of suspicious, like some malicious software (aka “malware”) is messing with your computer. I suggest scanning your Acer laptop with 3 malware/spyware/virus scanners. All 3 of these have free versions. So just download and use the free versions, no need to purchase anything.
Even if the first 2 find and remove threats to your PC, please still use the last one. Each program may catch threats to your PC that the others miss.