diff --git a/server/src/main/java/com/exacaster/lighter/application/sessions/SessionService.java b/server/src/main/java/com/exacaster/lighter/application/sessions/SessionService.java
index 80aadd0d..2123b95f 100644
--- a/server/src/main/java/com/exacaster/lighter/application/sessions/SessionService.java
+++ b/server/src/main/java/com/exacaster/lighter/application/sessions/SessionService.java
@@ -111,8 +111,4 @@ public Statement getStatement(String id, String statementId) {
     public Statement cancelStatement(String id, String statementId) {
         return statementHandler.cancelStatement(id, statementId);
     }
-
-    public Optional<Application> fetchPermanentSession() {
-        return Optional.ofNullable(sessionConfiguration.getPermanentSessionId()).flatMap(this::fetchOne);
-    }
 }
diff --git a/server/src/main/java/com/exacaster/lighter/backend/yarn/YarnBackend.java b/server/src/main/java/com/exacaster/lighter/backend/yarn/YarnBackend.java
index 8d9b28fe..cf820a30 100644
--- a/server/src/main/java/com/exacaster/lighter/backend/yarn/YarnBackend.java
+++ b/server/src/main/java/com/exacaster/lighter/backend/yarn/YarnBackend.java
@@ -1,6 +1,7 @@
 package com.exacaster.lighter.backend.yarn;
 
 import static java.util.stream.Stream.of;
+import static org.slf4j.LoggerFactory.getLogger;
 
 import com.exacaster.lighter.application.Application;
 import com.exacaster.lighter.application.ApplicationInfo;
@@ -22,11 +23,12 @@
 import java.util.Map;
 import java.util.Objects;
 import java.util.Optional;
-import org.springframework.http.HttpEntity;
+import org.slf4j.Logger;
 import org.springframework.security.kerberos.client.KerberosRestTemplate;
 
 public class YarnBackend implements Backend {
 
+    private static final Logger LOG = getLogger(YarnBackend.class);
     private static final String TOKEN_ENDPOINT = "/ws/v1/cluster/delegation-token";
 
     private final YarnProperties yarnProperties;
@@ -82,16 +84,20 @@ public String getSessionJobResources() {
     @Override
     public void kill(Application application) {
         var state = new State("KILLED");
-        getYarnApplicationId(application).ifPresent(
-                id -> getToken().ifPresentOrElse(t -> client.setState(id, state, t), () -> client.setState(id, state)));
+        // TODO remove after fixed
+        try {
+            getYarnApplicationId(application).ifPresent(id -> getToken()
+                    .ifPresentOrElse(t -> client.setState(id, state, t), () -> client.setState(id, state)));
+        } catch (Exception e) {
+            LOG.error("Can't kill Yarn app: {}", application, e);
+        }
     }
 
     private Optional<String> getToken() {
         var url = yarnProperties.getUrl() + TOKEN_ENDPOINT;
         var body = Map.of("renewer", "lighter");
         return kerberosRestTemplate
-                .map(it -> it.postForEntity(url, body, Token.class))
-                .map(HttpEntity::getBody)
+                .map(it -> it.postForObject(url, body, Token.class))
                 .map(Token::getToken);
     }
 
diff --git a/server/src/main/java/com/exacaster/lighter/backend/yarn/resources/Token.java b/server/src/main/java/com/exacaster/lighter/backend/yarn/resources/Token.java
index 16c08e90..e092c700 100644
--- a/server/src/main/java/com/exacaster/lighter/backend/yarn/resources/Token.java
+++ b/server/src/main/java/com/exacaster/lighter/backend/yarn/resources/Token.java
@@ -1,12 +1,18 @@
 package com.exacaster.lighter.backend.yarn.resources;
 
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+import com.fasterxml.jackson.annotation.JsonProperty;
 import io.micronaut.core.annotation.Introspected;
+import io.micronaut.core.annotation.Nullable;
 
 @Introspected
+@JsonIgnoreProperties(ignoreUnknown = true)
 public class Token {
     private final String token;
 
-    public Token(String token) {
+    @JsonCreator
+    public Token(@Nullable @JsonProperty("token") String token) {
         this.token = token;
     }
 
diff --git a/server/src/main/java/com/exacaster/lighter/rest/SessionController.java b/server/src/main/java/com/exacaster/lighter/rest/SessionController.java
index 018e3d8b..350a1ffb 100644
--- a/server/src/main/java/com/exacaster/lighter/rest/SessionController.java
+++ b/server/src/main/java/com/exacaster/lighter/rest/SessionController.java
@@ -62,11 +62,6 @@ public Optional<Application> get(@PathVariable String id) {
         return sessionService.fetchOne(id, true);
     }
 
-    @Get("/permanent")
-    public Optional<Application> getPermanent() {
-        return sessionService.fetchPermanentSession();
-    }
-
     @Delete("/{id}")
     public void delete(@PathVariable String id) {
         sessionService.deleteOne(id);
diff --git a/server/src/test/groovy/com/exacaster/lighter/application/sessions/SessionServiceTest.groovy b/server/src/test/groovy/com/exacaster/lighter/application/sessions/SessionServiceTest.groovy
index 46e55c59..a8af5f21 100644
--- a/server/src/test/groovy/com/exacaster/lighter/application/sessions/SessionServiceTest.groovy
+++ b/server/src/test/groovy/com/exacaster/lighter/application/sessions/SessionServiceTest.groovy
@@ -66,11 +66,5 @@ class SessionServiceTest extends Specification {
 
         then: "returns empty"
         session.isEmpty()
-
-        when: "fetch permanent"
-        session = service.fetchPermanentSession()
-
-        then: "returns empty"
-        session.isEmpty()
     }
 }
diff --git a/server/src/test/groovy/com/exacaster/lighter/rest/SessionControllerTest.groovy b/server/src/test/groovy/com/exacaster/lighter/rest/SessionControllerTest.groovy
index 38cede61..7ca4b3f3 100644
--- a/server/src/test/groovy/com/exacaster/lighter/rest/SessionControllerTest.groovy
+++ b/server/src/test/groovy/com/exacaster/lighter/rest/SessionControllerTest.groovy
@@ -47,7 +47,7 @@ class SessionControllerTest extends Specification {
     def "returns permanent session"() {
         when:
         def result = client.toBlocking()
-                .exchange(HttpRequest.GET("/sessions/permanent"), Map.class).body()
+                .exchange(HttpRequest.GET("/sessions/permanentSessionId"), Map.class).body()
 
         then:
         result.id == "permanentSessionId"