Always check on https://www.virustotal.com/ where you can upload the file for checking against all major antivirus software.
If you believe its a false positive (most likely for being the official LSPDFR download via the lcpdfr.com) lodge it for review by Microsoft at https://www.microsoft.com/en-us/wdsi/filesubmission. Microsoft will then review it (sometimes takes a few days) and then they will fix the classification.
I get the same classification on Windows 11. Have also just lodged it to Microsoft for manual review. Recommend not installing the file until Microsoft updates their classification or the LSPDFR development team fixes the reason for the flag.