I'm trying to Sign JWT Token using HMAC-SHA256 algorithm. For this I have created a keystore using Json Web key and trying to use in JWT Token profile. But getting following error on Save

java.lang.ClassCastException: class javax.crypto.spec.SecretKeySpec cannot be cast to class java.security.PublicKey (javax.crypto.spec.SecretKeySpec and java.security.PublicKey are in module java.base of loader 'bootstrap') 
	at com.pega.pegarules.session.external.authorization.KeystoreDataHandler.setKIDsForAliases(KeystoreDataHandler.java:340) ~[prenginext.jar:?] 
	at com.pega.pegarules.session.external.authorization.KeystoreDataHandler.initializeKeystore(KeystoreDataHandler.java:521) ~[prenginext.jar:?] 
	at com.pega.pegarules.session.internal.authorization.KeyStoreCacheImpl.put(KeyStoreCacheImpl.java:472) ~[prprivate-session.jar:?] 
	at com.pega.pegarules.session.internal.authorization.KeyStoreCacheImpl.loadKeyStoretoCache(KeyStoreCacheImpl.java:286) ~[prprivate-session.jar:?] 
	at com.pega.pegarules.session.internal.authorization.KeyStoreCacheImpl.loadKeyStoreIfKeyStoreNotCachedYet(KeyStoreCacheImpl.java:445) ~[prprivate-session.jar:?] 
	at com.pega.pegarules.session.internal.authorization.KeyStoreCacheImpl.getAliases(KeyStoreCacheImpl.java:453) ~[prprivate-session.jar:?] 
	at com.pega.pegarules.integration.engine.internal.util.KeyStoreUtilsImpl.getKeyStoreAliases(KeyStoreUtilsImpl.java:1071) ~[printegrint.jar:?] 
	at com.pega.pegarules.integration.engine.internal.security.jwt.JWTProfileValidatorImpl.checkAliasInKeystore(JWTProfileValidatorImpl.java:830) ~[printegrint.jar:?] 
	at com.pega.pegarules.integration.engine.internal.security.jwt.JWTProfileValidatorImpl.validateKeystoreAliasPassword(JWTProfileValidatorImpl.java:733) ~[printegrint.jar:?] 
	at com.pega.pegarules.integration.engine.internal.security.jwt.JWTProfileValidatorImpl.validateJwsGenerationTokenProfile(JWTProfileValidatorImpl.java:423) ~[printegrint.jar:?] 
	at com.pega.pegarules.integration.engine.internal.security.jwt.JWTProfileValidatorImpl.validateGenerationTokenProfile(JWTProfileValidatorImpl.java:115) ~[printegrint.jar:?] 
	at com.pega.pegarules.integration.engine.internal.security.jwt.JWTProfileValidatorImpl.validateTokenProfilePage(JWTProfileValidatorImpl.java:77) ~[printegrint.jar:?] 
	at com.pegarules.generated.activity.ra_action_validate_18d308885f64de23cd4f16349ca0104f.step2_circum0(ra_action_validate_18d308885f64de23cd4f16349ca0104f.java:273) ~[?:?] 
	at com.pegarules.generated.activity.ra_action_validate_18d308885f64de23cd4f16349ca0104f.perform(ra_action_validate_18d308885f64de23cd4f16349ca0104f.java:93) ~[?:?] 
	at com.pega.pegarules.session.internal.mgmt.Executable.doActivity(Executable.java:2872) ~[prprivate-session.jar:?] 

Please help