Something is trying to update one of my domains...

Sun Dec 24 06:07:23 UTC 2017

I have just discovered several entries of

Dec 24 06:26:49 dns1 named[16591]: update-security: error: client
+37.157.109.77#2936: update 'tdnet.eu/IN' denied

Which is realy bizzar, because this is the 4G/LTE IP of my ThinkPad T400
with Windows 7 Home Edition installed...

Can someone give me a hint what is trying to update  my  <tdnet.eu>  and
only this one?

In the logfiles I do not find more infos.

--
Michelle Konzack        Miila ITSystems @ TDnet
GNU/Linux Developer     00372-54541400