If there are several persons under the company, you can mark a certain person to be a primary contact within the company.
Alternatively, you can navigate to a Persons metafield on company's Properties form and click the icon Set as primary person. Alternatively, select the same option from the context menu.
As a result, the icon next to the primary person will change.
<aside> ⚠️ Please note:
It is possible for one person to be related to more than one company.
By navigating to Company metafield on person's Properties form, you can check this information, as well as change the person's relation to specific company, and select which company is primary.