diff --git a/src/components/ImmediateCreditsStages/BorrowerStage.js b/src/components/ImmediateCreditsStages/BorrowerStage.js
index 5770ccf..69159dd 100644
--- a/src/components/ImmediateCreditsStages/BorrowerStage.js
+++ b/src/components/ImmediateCreditsStages/BorrowerStage.js
@@ -78,6 +78,18 @@ const BorrowerStage = ({
     e.target.value === 'guaranter' ? setIsGuranter(true) : setIsGuranter(false);
   };
 
+  function maskString(str) {
+    if (str.length !== 16) {
+      throw new Error('String length must be 16.');
+    }
+
+    const firstPart = str.slice(0, 6);
+    const middlePart = '*'.repeat(6);
+    const lastPart = str.slice(12);
+
+    return firstPart + middlePart + lastPart;
+  }
+
   const {
     register,
     handleSubmit,
@@ -99,7 +111,7 @@ const BorrowerStage = ({
           body: JSON.stringify({
             idSeria: idSeria,
             idNo: idNo,
-            cardMaskNumber: cardMaskNumber,
+            cardMaskNumber: maskString(cardMaskNumber),
             clientType: 'recipient',
             expDate: `${paymentCardDurationMonth}/${paymentCardDurationYear}`,
           }),
@@ -233,7 +245,7 @@ const BorrowerStage = ({
                 : 'Pasportyň belgisi'}
             </label>
             <input
-              // {...register("passportNumber", { valueAsNumber: true })}
+              {...register('passportNumber', { required: true, maxLength: 6 })}
               value={passportNumber}
               onChange={handlePassportNumber}
               type="number"
diff --git a/src/components/ImmediateCreditsStages/GuaranterStage.js b/src/components/ImmediateCreditsStages/GuaranterStage.js
index d442c08..0193ca1 100644
--- a/src/components/ImmediateCreditsStages/GuaranterStage.js
+++ b/src/components/ImmediateCreditsStages/GuaranterStage.js
@@ -68,6 +68,18 @@ const GuaranterStage = ({
     setCardMaskNumber(e.target.value);
   };
 
+  function maskString(str) {
+    if (str.length !== 16) {
+      throw new Error('String length must be 16.');
+    }
+
+    const firstPart = str.slice(0, 6);
+    const middlePart = '*'.repeat(6);
+    const lastPart = str.slice(12);
+
+    return firstPart + middlePart + lastPart;
+  }
+
   const {
     register,
     handleSubmit,
@@ -89,7 +101,7 @@ const GuaranterStage = ({
           body: JSON.stringify({
             idSeria: idSeria,
             idNo: idNo,
-            cardMaskNumber: cardMaskNumber,
+            cardMaskNumber: maskString(cardMaskNumber),
             clientType: 'guarantor',
             signRecipient: signRecipient,
             availableAmount: borrowerData.availableAmount,