Teamviewer access blocked

I'm not overly technical but use Teamviewer to access daughter's laptop if she has a problem. She has a new Netgear D6000 router which steadfastly refuses to let Teamviewer connect. It even prevents access to www.teamviewer.com website.  I'm confident it is the router - another laptop on the same router has the same problem but using my phone on 4G to connect the laptop to the internet is fine.  There are no specific blocks in place on the router, i.e. nothing I have added but Teamviewer simply reports that it has no connection. A friend has suggested that a port may not be open but I really don't know how to go about doing so. Any help please?