DoS attack: Teardrop or derivative - WAN goes unresponsive every five minutes or so

I purchuased C7000V2 to avoid renting comcast router then after a couples of months using it I started to lose internet connection progressively till the point i started to reset the router every 5 mins  and I thought that was a comcast issue. I was trying to figuere out what was causing this issue for a week until i gave up and i called comcast yesterday.They came by and they didnt find anything wrong. then when i looked into the netgear router i found this  "[DoS attack: Teardrop or derivative] from 133.2.159.224, port 0 1 Wed Mar 13 14:24:42 2019 124.58.185.53:0 133.2.159.224:0" -----------Those IPs belongs to Japan and Korea ------- I think the best opptions to avoid this kind of issues is moving to a different rounter and rent a comcast router again since I dont see any way to avoid this and Netgear devices are prone to be hacked. 

Any idea what to do I will appriciate it .

Thanks

Kalin