To my knowledge there is no solution to solving this unless you get rid of the TK domain and either choose a forumotion domain name or buy a domain name from another source.
This is google choosing and tk domains are very dodgy and can do a lot of harm to your site.
The problem with TK domains is they aren't real domains. Instead they are known by "Virtual DNS" which in turn operates through IFrame which can cause many problems such as loss of traffic to your forum, timeouts and among other things. Honestly they aren't worth the hassle.