Company name not visible when trying to tag in Facebook comment

We had a customer that wanted to tag a company on Facebook, that she had used, but when she started typing the name, the company name would not appear.
Another friend was able to tag the company with no problem.
We suggested to try adding the @ sign in front of the name. The customer tried this and low and behold the company name appeared in the list of results.
When you add the @ sign, it Facebook treats the name as a “mention” and searches if the company or person is mentioned in another post and will return that result as a tagging link.