We confirm / confirmed receipt of your payment.
Probably the first, but there is no way of telling without any context. Without context, it could also be 'will confirm' or 'haven't been able to confirm'.
Teachers: We supply a list of EFL job vacancies

I confirm my costs would be between £1,500-£2,000 or I confirmed my costs would be between £1,500-£2,000 which one is correct?

anonymouswhich one is correct?

Both are correct; it depends on when the confirmation happened.