diff --git a/.github/workflows/contracts_unit_tests.yml b/.github/workflows/contracts_unit_tests.yml
new file mode 100644
index 0000000..a8e85d7
--- /dev/null
+++ b/.github/workflows/contracts_unit_tests.yml
@@ -0,0 +1,25 @@
+name: Unit tests
+
+on: [ push ]
+
+jobs:
+  unit-tests:
+    runs-on: ubuntu-latest
+    strategy:
+      max-parallel: 5
+
+    steps:
+      - uses: actions/checkout@v4
+      - name: "Setup Node.js"
+        id: setup-node
+        uses: actions/setup-node@v4
+        with:
+          node-version: 20
+          cache: 'npm'
+          cache-dependency-path: contracts/package-lock.json
+      - name: "Install Dependencies"
+        id: install
+        run: cd contracts && npm ci
+      - name: "Backend Unit tests"
+        run: |
+          cd contracts && npm run test
diff --git a/contracts/contracts/ChatOracle.sol b/contracts/contracts/ChatOracle.sol
index 95d531e..4de24f9 100644
--- a/contracts/contracts/ChatOracle.sol
+++ b/contracts/contracts/ChatOracle.sol
@@ -228,7 +228,6 @@ contract ChatOracle {
         string memory errorMessage
     ) public onlyWhitelisted {
         require(!isPromptProcessed[promptId], "Prompt already processed");
-        isPromptProcessed[promptId] = true;
         IChatGpt(callbackAddresses[promptId]).onOracleLlmResponse(
             promptCallBackId,
             response,
@@ -236,6 +235,10 @@ contract ChatOracle {
         );
     }
 
+    function markPromptAsProcessed(uint promptId) public onlyWhitelisted {
+        isPromptProcessed[promptId] = true;
+    }
+
     function getMessages(
         uint promptId,
         uint promptCallBackId
@@ -277,7 +280,6 @@ contract ChatOracle {
         string memory errorMessage
     ) public onlyWhitelisted {
         require(!isFunctionProcessed[functionId], "Function already processed");
-        isFunctionProcessed[functionId] = true;
         IChatGpt(functionCallbackAddresses[functionId]).onOracleFunctionResponse(
             functionCallBackId,
             response,
@@ -285,6 +287,10 @@ contract ChatOracle {
         );
     }
 
+    function markFunctionAsProcessed(uint functionId) public onlyWhitelisted {
+        isFunctionProcessed[functionId] = true;
+    }
+
     function createOpenAiLlmCall(uint promptCallbackId, IOracleTypes.OpenAiRequest memory config) public returns (uint i) {
         uint promptId = promptsCount;
         callbackAddresses[promptId] = msg.sender;
@@ -307,7 +313,6 @@ contract ChatOracle {
         string memory errorMessage
     ) public onlyWhitelisted {
         require(!isPromptProcessed[promptId], "Prompt already processed");
-        isPromptProcessed[promptId] = true;
         IChatGpt(callbackAddresses[promptId]).onOracleOpenAiLlmResponse(
             promptCallBackId,
             response,
@@ -315,6 +320,10 @@ contract ChatOracle {
         );
     }
 
+    function markOpenAiPromptAsProcessed(uint promptId) public onlyWhitelisted {
+        isPromptProcessed[promptId] = true;
+    }
+
     function createGroqLlmCall(uint promptCallbackId, IOracleTypes.GroqRequest memory config) public returns (uint i) {
         uint promptId = promptsCount;
         callbackAddresses[promptId] = msg.sender;
@@ -337,11 +346,14 @@ contract ChatOracle {
         string memory errorMessage
     ) public onlyWhitelisted {
         require(!isPromptProcessed[promptId], "Prompt already processed");
-        isPromptProcessed[promptId] = true;
         IChatGpt(callbackAddresses[promptId]).onOracleGroqLlmResponse(
             promptCallBackId,
             response,
             errorMessage
         );
     }
+
+    function markGroqPromptAsProcessed(uint promptId) public onlyWhitelisted {
+        isPromptProcessed[promptId] = true;
+    }
 }
diff --git a/contracts/test/ChatGpt.ts b/contracts/test/ChatGpt.ts
index 9bf799b..208d0b8 100644
--- a/contracts/test/ChatGpt.ts
+++ b/contracts/test/ChatGpt.ts
@@ -86,6 +86,7 @@ describe("ChatGpt", function () {
 
       await chatGpt.startChat("Hello");
       await oracle.connect(oracleAccount).addResponse(0, 0, "Hi", "");
+      await oracle.connect(oracleAccount).markPromptAsProcessed(0);
       await expect(
         oracle.connect(oracleAccount).addResponse(0, 0, "Hi", "")
       ).to.be.revertedWith("Prompt already processed");
diff --git a/contracts/test/ChatOracle.ts b/contracts/test/ChatOracle.ts
index 1bb1ebe..bc079d9 100644
--- a/contracts/test/ChatOracle.ts
+++ b/contracts/test/ChatOracle.ts
@@ -2,7 +2,7 @@ import {loadFixture,} from "@nomicfoundation/hardhat-toolbox/network-helpers";
 import {expect} from "chai";
 import {ethers} from "hardhat";
 
-describe("ChatGpt", function () {
+describe("ChatOracle", function () {
   // We define a fixture to reuse the same setup in every test.
   // We use loadFixture to run this setup once, snapshot that state,
   // and reset Hardhat Network to that snapshot in every test.
@@ -20,7 +20,8 @@ describe("ChatGpt", function () {
   describe("Deployment", function () {
     it("Can update attestation", async () => {
       const {oracle, owner, allSigners} = await loadFixture(deploy);
-      await oracle.addAttestation(allSigners[1].address, "attestation");
+      await oracle.connect(owner).updateWhitelist(allSigners[1], true);
+      await oracle.connect(allSigners[1]).addAttestation("attestation");
 
       const attestationOwner = await oracle.latestAttestationOwner();
       const attestation = await oracle.attestations(attestationOwner);
@@ -30,8 +31,8 @@ describe("ChatGpt", function () {
       const {oracle, owner, allSigners} = await loadFixture(deploy);
 
       await expect(
-        oracle.connect(allSigners[1]).addAttestation(allSigners[1].address, "attestation")
-      ).to.be.rejectedWith("Caller is not owner");
+        oracle.connect(allSigners[1]).addAttestation("attestation")
+      ).to.be.rejectedWith("Caller is not whitelisted");
     });
   });
 });