docs: fix error messages

README.md

@@ -78,18 +78,18 @@ You will see:
   "statusCode": 400,
   "body": [
     {
-      "message": "The amortization received is invalid.",
-      "information": "The amortization must be a number greater than 0 but undefined was received instead.",
+      "message": "The amortization is invalid.",
+      "information": "The amortization must be a number greater than 0 but \"undefined\" was received instead.",
       "code": 400
     },
     {
-      "message": "The payment schedule received is invalid.",
-      "information": "The payment schedule must be a non-null string but undefined was received instead.",
+      "message": "The payment schedule is invalid.",
+      "information": "The payment schedule must be a non-null string but \"undefined\" was received instead.",
       "code": 400
     },
     {
       "message": "The nominalInterestRate is invalid.",
-      "information": "The nominalInterestRate must be a number greater than 0 but undefined was received instead.",
+      "information": "The nominalInterestRate must be a number greater than 0 but \"undefined\" was received instead.",
       "code": 400
     }
   ]
@@ -199,4 +199,4 @@ fetch('http://localhost:3000/mortgage', {
 .then(console.log)
 ```
 
-If you have any questions or suggestions, please open an [issue](https://github.com/EricRibeiro/mortgage-calculator-service/issues) or [pull request](https://github.com/EricRibeiro/mortgage-calculator-service/pulls) ❤️
+If you have any questions or suggestions, please open an [issue](https://github.com/EricRibeiro/mortgage-calculator-service/issues) or [pull request](https://github.com/EricRibeiro/mortgage-calculator-service/pulls) ❤️