If you cannot scan any Reolink cameras in the LAN(already connected to the network) on the Reolink Client(Win OS), please kindly check if the Reolink Client is allowed through the Windows Firewall with following steps:
Step 1. Click on icon on the left corner on your PC and tap on Settings –> Network and Internet –> Windows Firewall page to click Firewall & network protection->Allow an app through Firewall.
Step 2. Click the Change settings button and tick on Reolink Client, then tick on Private and Public( optional), click OK to save.
Note: If you have installed any antivirus software, try to close them to check.