No internet

I'm using Bitdefender total security already for several years. The last few months my family members are complaining about no WIFI/Network. Sometimes a reboot of the computer was needed to get network back. Within that time I've also upgrade my Unifi network so my focus on trouble shooting was on the Unifi network. This week I've found out by making traces on the AP of Unifi that in case of no network from a computer, the computer was sending ip packets(TCP) to the network and the responses where also send back over the network to the computer however the computer was not reacting on that. I've tried also to ping from the computer to ping the gateway. In the pcap trace which I've made on the UniFi AP a saw that the ping request from computer to gateway and also ping responses back to computer however it looked like the computer didn't received the responses. Till I've turned off all the settings in Bitdefender and then the network came reachable again.

My question on here is, which parameter/setting in Bitdefender is causing this strange/unpredictable behaviour. My children are doing now a days there exams from home so the network and computer must have 100% network connectivity otherwise they will fail the exam. At this moment I think to deinstall all the Bitdefender from their computer but I think it is just a setting in Bitdefender to prevent issues which I've described.