Openvas: WARNING: (ospd_openvas.daemon) The vt 1.3.6.1.4.1.25623.1.0.144540 was not found and it will not be loaded

GVM versions

gsad: (‘gsad --version’) Greenbone Security Assistant 9.0.1
gvmd: (‘gvmd --version’) Greenbone Vulnerability Manager 9.0.1
openvas-scanner: (‘openvas --version’, in older GVM versions < 11: ‘openvassd --version’) OpenVAS 7.0.1
gvm-libs: gvm-libs 11.0.1

Environment

Operating system: Ubuntu 20.04.1 LTS
Kernel: (‘uname -a’) 5.4.0-47-generic #51-Ubuntu SMP
Installation method / source: PPA by mohamed razavi

Durin a scan I’m getting messages like:

Oct 22 14:58:18 netz-secscan OSPD - openvas: WARNING: (ospd_openvas.daemon) The vt 1.3.6.1.4.1.25623.1.0.892799 was not found and it will not be loaded.
Oct 22 14:58:19 netz-secscan OSPD - openvas: WARNING: (ospd_openvas.daemon) The vt 1.3.6.1.4.1.25623.1.0.892798 was not found and it will not be loaded.

About 40-50 vt’s are mentioned. Why? How do I fix this?