IntelliJ giving "cannot resolve symbol"

 Intellij keeps giving "can not resolve symbol" when actually there is not a dependency problem as it can actually build the problem. By searching on the internet I found that some people recommend to invalidate the cache,  but I tried several times and the issue does not get solved. I am using 

IntelliJ IDEA 2017.3 EAP (Ultimate Edition)
Build #IU-173.3415.22, built on October 25, 2017
IntelliJ IDEA EAP User
Expiration date: November 24, 2017
JRE: 1.8.0_152-release-1024-b6 amd64
JVM: OpenJDK 64-Bit Server VM by JetBrains s.r.o
Windows 10 10.0

I have also tried version 2017.2.5 and I have the same issue. This picture shows the issue:

Thanks in advance.