Most likely, you have an environment variable configured which has the priority over the. If the JDK version in the About dialog doesn't match or didn't change, see below.Notice the vendor (should be JetBrains s.r.o) and the release number (should correspond to the number after b in the file you've downloaded). Verify via About dialog that the new runtime is used.
Installing old runtime versions may render your IDE unusable or introduce new issues. It makes sense to install the most recent version or the version you were asked to try by JetBrains staff. All platforms: download and install JetBrains Runtime via Choose Boot Java Runtime for the IDE action
Our IDEs will not run on the older Java versions like Java 8.
Please note that all the current IDE versions require at least Java 11 version to run. If you need to change the runtime to a different version, see below. All the products on all the supported platforms already have 64-bit JetBrains Runtime 11 bundled and it will be used by default to run the IDE.