NullPointerException in TupleSetsImpl.setNextTuple if a particular 'NOT' condition in a certain rule is not on top in the order

Got the below execution time error with the Drools version 7.68.0.Final. I was able to get over the error by reordering the condition sequence of a certain rule (brought a NOT condition to the top) though it is not a clean way. Please look into the issue and let me know in case of any questions. Thanks

 java.lang.NullPointerException] with root cause
java.lang.NullPointerException: null
        at org.drools.core.common.TupleSetsImpl.setNextTuple(TupleSetsImpl.java:349) ~[drools-core-7.68.0.Final.jar!/:7.68.0.Final]
        at org.drools.core.common.TupleSetsImpl.removeInsert(TupleSetsImpl.java:167) ~[drools-core-7.68.0.Final.jar!/:7.68.0.Final]
        at org.drools.core.phreak.RuleNetworkEvaluator.doRiaNode2(RuleNetworkEvaluator.java:705) ~[drools-core-7.68.0.Final.jar!/:7.68.0.Final]
        at org.drools.core.phreak.RuleNetworkEvaluator.innerEval(RuleNetworkEvaluator.java:334) ~[drools-core-7.68.0.Final.jar!/:7.68.0.Final]
        at org.drools.core.phreak.RuleNetworkEvaluator.doRiaNode(RuleNetworkEvaluator.java:631) ~[drools-core-7.68.0.Final.jar!/:7.68.0.Final]
        at org.drools.core.phreak.RuleNetworkEvaluator.evalBetaNode(RuleNetworkEvaluator.java:554) ~[drools-core-7.68.0.Final.jar!/:7.68.0.Final]
        at org.drools.core.phreak.RuleNetworkEvaluator.evalNode(RuleNetworkEvaluator.java:386) ~[drools-core-7.68.0.Final.jar!/:7.68.0.Final]
        at org.drools.core.phreak.RuleNetworkEvaluator.innerEval(RuleNetworkEvaluator.java:346) ~[drools-core-7.68.0.Final.jar!/:7.68.0.Final]
        at org.drools.core.phreak.RuleNetworkEvaluator.outerEval(RuleNetworkEvaluator.java:182) ~[drools-core-7.68.0.Final.jar!/:7.68.0.Final]
        at org.drools.core.phreak.RuleNetworkEvaluator.evaluateNetwork(RuleNetworkEvaluator.java:140) ~[drools-core-7.68.0.Final.jar!/:7.68.0.Final]
        at org.drools.core.phreak.RuleExecutor.reEvaluateNetwork(RuleExecutor.java:235) ~[drools-core-7.68.0.Final.jar!/:7.68.0.Final]
        at org.drools.core.phreak.RuleExecutor.fire(RuleExecutor.java:179) ~[drools-core-7.68.0.Final.jar!/:7.68.0.Final]
        at org.drools.core.phreak.RuleExecutor.evaluateNetworkAndFire(RuleExecutor.java:110) ~[drools-core-7.68.0.Final.jar!/:7.68.0.Final]
        at org.drools.core.concurrent.AbstractRuleEvaluator.internalEvaluateAndFire(AbstractRuleEvaluator.java:33) ~[drools-core-7.68.0.Final.jar!/:7.68.0.Final]
        at org.drools.core.concurrent.SequentialRuleEvaluator.evaluateAndFire(SequentialRuleEvaluator.java:43) ~[drools-core-7.68.0.Final.jar!/:7.68.0.Final]
        at org.drools.core.common.DefaultAgenda.fireLoop(DefaultAgenda.java:869) ~[drools-core-7.68.0.Final.jar!/:7.68.0.Final]
        at org.drools.core.common.DefaultAgenda.internalFireAllRules(DefaultAgenda.java:816) ~[drools-core-7.68.0.Final.jar!/:7.68.0.Final]
        at org.drools.core.common.DefaultAgenda.fireAllRules(DefaultAgenda.java:808) ~[drools-core-7.68.0.Final.jar!/:7.68.0.Final]
        at org.drools.core.impl.StatefulKnowledgeSessionImpl.internalFireAllRules(StatefulKnowledgeSessionImpl.java:1341) ~[drools-core-7.68.0.Final.jar!/:7.68.0.Final]
        at org.drools.core.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:1332) ~[drools-core-7.68.0.Final.jar!/:7.68.0.Final]
        at org.drools.core.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:1316) ~[drools-core-7.68.0.Final.jar!/:7.68.0.Final]
        at org.drools.core.impl.StatelessKnowledgeSessionImpl.execute(StatelessKnowledgeSessionImpl.java:265) ~[drools-core-7.68.0.Final.jar!/:7.68.0.Final]