diff --git a/packages/relay/tests/lib/services/hbarLimitService/hbarLimitService.spec.ts b/packages/relay/tests/lib/services/hbarLimitService/hbarLimitService.spec.ts
index c39ffe7f6..048e0a39e 100644
--- a/packages/relay/tests/lib/services/hbarLimitService/hbarLimitService.spec.ts
+++ b/packages/relay/tests/lib/services/hbarLimitService/hbarLimitService.spec.ts
@@ -24,7 +24,6 @@ import { AccountId, Hbar } from '@hashgraph/sdk';
 import chai, { expect } from 'chai';
 import chaiAsPromised from 'chai-as-promised';
 import { randomBytes, uuidV4 } from 'ethers';
-import { Long } from 'long';
 import pino, { Logger } from 'pino';
 import { Counter, Gauge, Registry } from 'prom-client';
 import sinon from 'sinon';
@@ -189,12 +188,13 @@ describe('HBAR Rate Limit Service', function () {
   });
 
   describe('shouldLimit', function () {
-    const operatorEnvs = [{ OPERATOR_ID_MAIN: ConfigService.get('OPERATOR_ID_MAIN') }, { OPERATOR_ID_MAIN: null }];
+    const operatorEnvs = [
+      { OPERATOR_ID_MAIN: ConfigService.get('OPERATOR_ID_MAIN') },
+      { OPERATOR_ID_MAIN: zeroAddress() },
+    ];
 
     operatorEnvs.forEach((operatorEnv) => {
-      const operatorAddress = operatorEnv.OPERATOR_ID_MAIN
-        ? prepend0x(AccountId.fromString(operatorEnv.OPERATOR_ID_MAIN).toSolidityAddress())
-        : zeroAddress();
+      const operatorAddress = AccountId.fromString(operatorEnv.OPERATOR_ID_MAIN).toSolidityAddress();
 
       withOverriddenEnvsInMochaTest(operatorEnv, () => {
         describe('based on evmAddress', async function () {
diff --git a/packages/relay/tests/lib/utils.spec.ts b/packages/relay/tests/lib/utils.spec.ts
index 4d97d1198..973b921ac 100644
--- a/packages/relay/tests/lib/utils.spec.ts
+++ b/packages/relay/tests/lib/utils.spec.ts
@@ -199,15 +199,10 @@ describe('Utils', () => {
         OPERATOR_KEY_MAIN: privateKeys[0].keyValue,
       },
       () => {
-        it('should return null and log a warning if operatorId is missing', () => {
-          const warnSpy = sinon.spy(logger, 'warn');
-
-          const operator = Utils.getOperator(logger);
-
-          expect(operator).to.be.null;
-          expect(warnSpy.calledOnce).to.be.true;
-          expect(warnSpy.firstCall.args[0]).to.equal('Invalid operatorId or operatorKey for main client.');
-          warnSpy.restore();
+        it('should throw error if operatorId is missing', () => {
+          expect(() => Utils.getOperator(logger)).to.throw(
+            'Configuration error: OPERATOR_ID_MAIN is a mandatory configuration for relay operation.',
+          );
         });
       },
     );