Issue DNS-Slave Manager Problems Bind9

[Consertis]

Hello,
I am new to the forum, so please excuse me if not all the necessary data is posted directly.

I was planning to set up a slave DNS server and also created everything according to the Official Plesk Guide. The firewall has also been adjusted and the respective ports are open.
But now I get the following error message from Bind(9), when trying to restart bind and get the status output:

Loaded: loaded (/lib/systemd/system/named.service; enabled; vendor preset: enabled)
Active: active (running) since Thu 2022-03-17 14:27:03 UTC; 3min 32s ago
Docs: man:named(8)
Main PID: 106101 (named)
Tasks: 8 (limit: 2262)
Memory: 15.8M
CGroup: /system.slice/named.service
└─106101 /usr/sbin/named -f -4 -u bind

Mar 17 14:27:03 tu2040 named[106101]: managed-keys-zone: loading from master file managed-keys.bind failed: unexpected end of input
Mar 17 14:27:03 tu2040 named[106101]: managed-keys-zone: loaded serial 5
Mar 17 14:27:03 tu2040 named[106101]: zone 0.in-addr.arpa/IN: loaded serial 1
Mar 17 14:27:03 tu2040 named[106101]: zone 127.in-addr.arpa/IN: loaded serial 1
Mar 17 14:27:03 tu2040 named[106101]: zone localhost/IN: loaded serial 2
Mar 17 14:27:03 tu2040 named[106101]: zone 255.in-addr.arpa/IN: loaded serial 1
Mar 17 14:27:03 tu2040 named[106101]: all zones loaded
Mar 17 14:27:03 tu2040 named[106101]: running
Mar 17 14:27:13 tu2040 named[106101]: managed-keys-zone: Unable to fetch DNSKEY set '.': timed out
Mar 17 14:27:13 tu2040 named[106101]: resolver priming query complete

The Plesk Server is hostet by an Hoster.
The DNS-Slave Server is hosted internally at my place but has internet connection and a static IP-Adress.

I really dont know what i could do to prevent this happening or why it happened at all and would appreciate any help.

Thanks in Advance

 

[QuantumBreak]

Did you found a solution?
I have the same problem for a while and cant find any solution.