Violation of PRIMARY KEY constraint 'PK__Transact__'. Cannot insert duplicate key in object 'dbo.Transactions_ID'. The duplicate key value is (1001) - sql

Question

When I am trying to insert execute the table and I am getting that error. And when I try to insert more rows into Employee_in I get an error
The number of columns for each row in a table value constructor must be the same
CREATE DATABASE EmployeeDatabase
USE EmployeeDatabase
CREATE TABLE Employee_In
(
EmployeeID INT NOT NULL PRIMARY KEY,
EmployeeName CHAR(30) NOT NULL,
EmployeeCountry CHAR(30)NOT NULL,
EmployeeSalary INT NOT NULL
)
USE EmployeeDatabase
GO
INSERT INTO Employee_In (EmployeeID, EmployeeName, EmployeeCountry, EmployeeSalary)
VALUES (1001, 'Sundar', 'USA', 125000),
(1002, 'Satya', 'CANADA', 120000);
SELECT * FROM Employee_In
CREATE TABLE Transactions_ID
(
TransactionID INT NOT NULL PRIMARY KEY,
EmployeeID INT FOREIGN KEY REFERENCES Employee_In(EmployeeID),
PostalDate VARCHAR(20) NOT NULL,
Amount VARCHAR(40) NOT NULL,
Description CHAR(25),
);
USE EmployeeDatabase
GO
INSERT INTO Transactions_ID (TransactionID, EmployeeID, PostalDate, Amount)
VALUES ('1001','1001','2020-04-07','20000')

Answer 1

Violation of PRIMARY KEY constraint 'PK__Transact__'. Cannot insert duplicate key in object 'dbo.Transactions_ID'. The duplicate key value is (1001)
This means you already have a value 1001 for the PK TransactionID in your table, most likely from and earlier insert.
INSERT INTO Transactions_ID (TransactionID, EmployeeID, PostalDate, Amount)
VALUES ('1001', '1001', '2020-04-07', '20000')
Here you are trying to insert string in columns with a datatype int... this should be:
INSERT INTO Transactions_ID (TransactionID, EmployeeID, PostalDate, Amount)
VALUES (1001, 1001, '2020-04-07', '20000')
Good luck!