an error occurred while searching for cover art.

[pugnari]

Hi.

When I try to add a cover art via the web interface, Subsonic gives me the error message

"Sorry, an error occurred while searching for cover art."

although some images from last.fm are already suggested, which looks strange.
If I look up the log file, it records the following error

[2021-05-10 16:00:32,731] WARN FanartTvService - Failed to get artist images from fanart.tv
java.lang.NoClassDefFoundError: sun/security/ec/ECParameters
at sun.security.pkcs11.SunPKCS11$P11Service.newInstance0(SunPKCS11.java:1038)
at sun.security.pkcs11.SunPKCS11$P11Service.newInstance(SunPKCS11.java:980)
at sun.security.jca.GetInstance.getInstance(GetInstance.java:236)
at sun.security.jca.GetInstance.getInstance(GetInstance.java:164)
at java.security.Security.getImpl(Security.java:694)
at java.security.AlgorithmParameters.getInstance(AlgorithmParameters.java:146)
at sun.security.x509.AlgorithmId.decodeParams(AlgorithmId.java:121)
...[many more lines]

I only understand that this is java related error,
and don't know how to fix this. Could anyone kindly give me a suggestion?

Version 6.1.6 (build 0cfa60) – November 10, 2019
Server jetty-6.1.x, java 1.7.0_261, HSQLDB, Linux (68.9 MB / 138.0 MB)