You’ll need to identify spam in order to get it removed. That can be done quite easily.
First, perform a Google search for the term that you wish to eradicate the Google My Business name spam from. Navigate to Google’s three pack and click on ‘View all’ to see more listings.
Have a look at the listings and make a list of listings that you find suspicious.
To check whether the listing name matches the business’s actual name, go to their website by clicking on the website link that they’ve provided.
The name that you see on their website would be their real-world business name. If you’re not sure where to look in the website, their homepage title would most-probably have their business name. Otherwise, check for their logo and footer.
Once you identify the spammers (accidental or deliberate), the first thing I suggest you do is ‘Suggest an edit.’
There’s a good chance for that spam to be intentional, but there’s also a fair chance of it being accidental. Suggest an edit and see if the business fixes it.
Although, if they don’t or if you have a feeling that the business needs some action taken against, you can submit a complaint in Google’s Business Redressal Form.
Raising your issue via the Redressal Form will take your query to a reviewer, a human reviewer, and not leave it up to bots and algorithms. You can submit all your findings in this form. Attach some screenshots to help the reviewer with the process, and if all is in order to what you’ve found, Google will take actions against that listing.