Your (My) comprehension .
... is based on what you wrote ... and the details did not specify how many products you were importing reviews for. Unfortunately, mind reading is not one of my talents. LOL
I did not write that I am importing reviews for 100 products.
I didn't say you did. That was an "example" ... now we're back to the comprehension problem again ... lol
This does not happen any of my 6 sites or anyone elses site that I have heard of so I doubt it is a problem with the plugin. In these cases it's usually user error ... i.e the user has done something stupid or messed up the settings somehow. It's impossible to say what that may be without actually looking at what you have done.
Your best course of action is to write to support and give them admin access to your site so they can look for the problem. Create a new user/password with admin rights ... tell them what it is in your email ... then delete it after they have fixed the problem.
Good Luck