The Report of Foreign Bank and Financial Accounts (FBAR) is an annual report.
If I understand your question, you filed an FBAR in April 2021 for the year ended 31 December 2020.
Sometime in 2021, the value of your account went over $10,000. That would be included in an FBAR filing for the 2021 year, due 15 April 2022.
For more info see: Report of Foreign Bank and Financial Accounts (FBAR)