diff --git a/index.js b/index.js
index d43966c..731a15b 100644
--- a/index.js
+++ b/index.js
@@ -168,29 +168,53 @@ function calculateBaseBillAmountAuto(detailSplitted, customKeywords, productKeyv
 function calculateBaseBillAmount(detailSplitted, customKeywords, productKeyval, billCount) {
     if (
         !productKeyval
-        || !Array.isArray(productKeyval)
-        || !productKeyval.KEYWORD_TOTALTAG 
+        || !productKeyval.KEYWORD_TOTALTAG
         || !productKeyval.KEYWORD_ADMINFEE
     ) {
         return calculateBaseBillAmountAuto(detailSplitted, customKeywords, productKeyval, billCount);
     }
-
+    
     const billCountOrDefault = billCount || 1;
 
     const totalTagihanKeyword = productKeyval.KEYWORD_TOTALTAG;
     if (!totalTagihanKeyword) return 0;
 
-    const totalTagihanItem = detailSplitted.find((item) => (item.keyword || '').toUpperCase() === totalTagihanKeyword);
+    const totalTagihanItem = detailSplitted.find((item) => (item.keyword || '').toUpperCase() === totalTagihanKeyword.toUpperCase());
     const totalTagihanValue = Number((totalTagihanItem.value || '').trim().replace(/^rp */i, '').replace(/\./g, ''));
-    if (!totalTagihanValue) return 0;
+    if (!totalTagihanValue) {
+        if (process.env.DEBUG_IRS_CALCULATE_BASE_BILL_AMOUNT) {
+            // eslint-disable-next-line no-console
+            console.log('=========== MISSING totalTagihanValue D7282FA7');
+        }
+        
+        return 0;
+    }
 
     const defaultAdminFee = Number(productKeyval.ADMINFEE || '');
 
     const adminFeeKeyword = productKeyval.KEYWORD_ADMINFEE;
-    if (!adminFeeKeyword && defaultAdminFee) return totalTagihanValue - (defaultAdminFee * billCountOrDefault);
-    if (!adminFeeKeyword) return 0;
+    if (!adminFeeKeyword && defaultAdminFee) {
+        if (process.env.DEBUG_IRS_CALCULATE_BASE_BILL_AMOUNT) {
+           // eslint-disable-next-line no-console
+           console.log('======== TOTAL TAGIHAN VALUE - (DEFAULT ADMIN FEE * BILL COUNT) D35E56AD') ;
+        }
+        return totalTagihanValue - (defaultAdminFee * billCountOrDefault);
+    }
 
-    const adminFeeItem = detailSplitted.find((item) => (item.keyword || '').toUpperCase() === adminFeeKeyword);
+    if (!adminFeeKeyword) {
+        if (process.env.DEBUG_IRS_CALCULATE_BASE_BILL_AMOUNT) {
+            // eslint-disable-next-line no-console
+            console.log('======== Missing adminFeeKeyword');
+        }
+
+        return 0;
+    }
+
+    const adminFeeItem = detailSplitted.find((item) => (item.keyword || '').toUpperCase() === adminFeeKeyword.toUpperCase());
+    if (process.env.DEBUG_IRS_CALCULATE_BASE_BILL_AMOUNT) {
+        // eslint-disable-next-line no-console
+        console.log(`======== adminFeeItem: ${adminFeeKeyword}`, adminFeeItem);
+    }
     const adminFeeValue = Number((adminFeeItem.value || '').trim().replace(/^rp */i, '').replace(/\./g, ''));
     if (!adminFeeValue) return 0;
 
diff --git a/test/main.js b/test/main.js
index 486aa17..671c3fc 100644
--- a/test/main.js
+++ b/test/main.js
@@ -179,6 +179,13 @@ describe('#irs', function() {
             splitted.find((item) => item.keyword === 'TAGIHAN').value.should.equal('131560');
             splitted.find((item) => item.keyword === 'DENDA').value.should.equal('9000');
         });
+        
+        it('should return correct result - tajira', () => {
+            const splitted = irs.splitPostpaidDetail('REFID:20770812/NAMA:SALWA AZ ZAHRA/CABANG:1012-DEPOK/Periode:1/Admin:2500/TOTALBAYAR:28.000');
+            // console.log(splitted);
+            splitted.find((item) => item.keyword === 'REFID').value.should.equal('20770812');
+            splitted.find((item) => item.keyword === 'Admin').value.should.equal('2500');
+        });
     });
 
     describe('#calculateBaseBillAmount', () => {
@@ -214,6 +221,16 @@ describe('#irs', function() {
                 // },
                 // 1
             ).should.equal(10140);
+
+            irs.calculateBaseBillAmount(
+                irs.splitPostpaidDetail('REFID:20770812/NAMA:SALWA AZ ZAHRA/CABANG:1012-DEPOK/Periode:1/Admin:2500/TOTALBAYAR:28.000'),
+                null,
+                {
+                    KEYWORD_TOTALTAG: 'TOTALBAYAR',
+                    KEYWORD_ADMINFEE: 'Admin',
+                },
+                1
+            ).should.equal(25500);
         });
     });