Answer:
To reverse the transaction, the journal entry is:
Date Account title Debit Credit
March 4, 2021 Accounts receivable - Megan Gray $5,800
Allowance for doubtful accounts $5,800
To record the receipt of cash:
Date Account title Debit Credit
March 4, 2021 Cash $5,800
Accounts receivable - Megan Gray $5,800