Unreal engine 4.18 no longer available?!

Hi, today when i started up the epic games launcher to continue working on my project i found out that the engines tab said 4.20 install instead of the typical 4.18 installed. When i checked to see the engines i saw that 4.18 was the only version i could not choose. Then when i looked at the size of all the engines installed it said 0.0 B which means that it is not installed… I dont know how it must have uninstalled on its own and why i cant choose to install it again! I can choose any other engine version except for that one which all my projects are using. The thing is that when i try to start up a project it starts normally just as if i had the engine installed and when i check my hard drive space, it is still the same as yesterday which means that the engine is still installed but somehow epic games thinks it isn’t… The major problem here is that i cant start any new projects or do anything at all that isn’t related to already existing project files.
What can be causing this error? Is there a way to fix it?! Thank you in advanced.

Ok, new update, this problem is definitely only related with the epic games launcher since i just restarted it and the engine version 4.18 apeared again but when i pressed start i popped away and changed by a install engine button and once again it wasnt on the choose engine tab….