For the review: open your Business Profile, go to Read reviews, hit Report next to the review, pick a reason, and send it. Google doesn't publish the full menu of reasons. Its help page gives two examples, Spam and Profanity, and you see the whole list when you open the menu.
The advice we can point to is general. Pick the closest match, wait three days, and if the review is still up, appeal it with a lot of detail. That's Stefan Somborac, a moderator on the Local Search Forum. The flag menu has no free-text box, so your first report is a category and no argument at all (Sterling Sky). The argument waits for the appeal. The appeal names a policy too, and a mismatch there can waste the one appeal you get.
For the profile: in the Maps app, open Business, then Reviews, then tap the reviewer's name. In the profile, tap More, then Report, then pick a reason. Google's examples there are Legal issue and Privacy concerns. Screenshot the profile name and photo before you file. Google may remove, restrict, or disable a profile name or photo that breaks its policies, and if it does, your screenshot is what's left to point to. Google says to be patient. A profile can take several days to assess.
For the review, Google says evaluation typically takes several days, and the Reviews Management Tool shows the status. "Decision pending" means Google hasn't evaluated it yet. "Report reviewed - no policy violation" means Google looked and found none. That's when you get one more move, the appeal, and it's where you finally get to write the argument out.
For impersonation the argument is narrow. Say who the account presents itself as. Show where it does that, in the profile name, the photo, or the review's own words. Then name which half of the policy it matches. Either it poses as a person, group, or organization, or it claims to be a verified authority. Once the appeal is in, the status changes to "Escalated - check your email for updates," and Google emails you the final decision. We walk through appealing a denied Google review report step by step. One appeal per review, ever. Our read is that the policy named has to match the argument. So the filing is the whole job.