[ubuntu] Domain dosen't work after time ...

Hey Guys.

I have a problem, but first sorry for my bad english!

So my problem is:

I created a site with apache and wordpress.

There were no problems after it!

I edit the whole website for arround 7 days and still no problem!

I reached the website with one of the two IP's from my vServer.

Then i coectet my domain with my second IP (the IP for the website)!

After this, my website was reachable from example.de.

After 1 day, the website wasn't reachable!!

I tried it with a my teamspeak3 server.

I coected the domain with the ts3 server long time ago.

I tried to coect with ts3.example.de, but there was a error, that teamspeak caot resolve the IP (domain)!

I don't know where the problem could be....

I have a vServer and a .de Domain on a other hoster.

I would be very happy if someone could help me out with this problem ... but please keep it easy as possible - im new in the apache/inteet scene!

Greatings

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