need help trying to figure out why my balance sheet isnt balancing. thank you

During June 202X, the business completed these transactions: June 1: Began the business with an investment of $8100 cash in exchange for common shares June 1: Purchased a computer for a total of $7200 by signing a note payable. Interest of 5% to be paid with the note payable on January 1 next year. The computer is expected to last 5 years. June 5: Purchased office supplies on account for $4950. June 9: Invoiced a client for services performed, $2700. June 13: Received $630 cash from a customer to clear the balance owing on their account. June 20: Received a $1080 bill for advertising for a campaign that had been run during the month. June 23: Paid $2250 of a bill received earlier in the month. June 25: Performed services for clients and received $4500 in cash. June 30: Declared and paid a cash dividend of $1350. June 30: A physical count revealed that $900 worth of supplies are still on hand. June 30: Paid $180 for the month's office rent. Employee salaries were also accrued. Employees work 5 days each week and are paid $4500 every Friday. The month ended on a Thursday