How to Set the Nat Type to Open ?

[Original.Classic]

Hello Guys. I Have a Problem with the NAT Type. I have the Nat Type Moderat. nut my Friend have it Open. Now i cant Join him and He Cant Join me -_- who can i fix it ? thanks for anny Help.
P.s I have a Fritzbox Home Server

[Shichiya]

Login into your ip address(default is 192.168.1.1)
Go to advance tab
Go to NAT tab
Go to Virual server tab
Set up the following
Type in any name for the individual port(e.g. R6S server/RainbowSix etc.)
TCP:80,443
UDP:10000-10099,3658,6115
at the ip address type in your ipv4 or something,go check on your network tab
Done.
In case it's still strict
Go to Service tab,Check if UPnP are enabled(mine disabled by default)
If UPnP is enabled,please disable>apply>enable>apply>restart your router
If problem still exist,go to google and look for help

[Shichiya]

Also,in case you don't know,casual matchmaking are still available,only custom match/terrorist hunt cannot be played together