Commercial use limit

For standard LinkedIn accounts, you can reach your commercial use limit after 1000 profile visits which means that after that you cannot view or visit profiles anymore. This limit resets every month. 

On Premium accounts like Sales Navigator, there is no commercial use limit. It is explained in detail in this LinkedIn article here:

Once you reach your commercial use limit, you can either use Dux-Soup X-Ray function to look for profiles or try to connect with profiles by joining LinkedIn groups. To learn more how to use LinkedIn groups with Dux-Soup, read our article here