Eclipse comment auto-completion doesn't work

Question

Auto generation/completion for comments is not working in my eclipse Photon workspace. At the moment I have resetted the code templates to defaults, which didn't help. To illustrate my problem consider a method that was just written and should now get documented:

/**
public FileEntry removeFileEntry(int index) {
    return files.remove(index);
}

So after typing in the beginning of a docstring comment, one should be able to let e.g. the '@return' tag generate automatically and the comment should be closed automatically as well. However, I'm getting this result:

/**
 * 
public FileEntry removeFileEntry(int index) {
    return files.remove(index);
}

So somehow my auto-completion stopped working, and I'm not able to relate this problem to any specific settings I changed since it last worked.

Can you help me with getting automatic/semi-automatic comment generation working again?

Using "Source -> Generate Element Comment" is working as expected. The result is:

/**
 * @param index
 * @return
 */
public FileEntry removeFileEntry(int index) {
    return files.remove(index);
}