My return was submitted and accepted by IRS and the payment was taken by IRS. but my return is still not processed on my account on IRS website. What should I do?

There is nothing for you to do ... because of the covid shut down earlier this year the IRS is still playing catch up.  Due to the reduced staffing the stimulus checks and returns with refunds were given top priority and the returns with balance dues were put on the back burner.   Eventually they will all be processed ... so as long as they accepted the payment there is really nothing you can do to speed up the process.