Pension contributions where relevant earnings are below the personal allowance

Is it true that if relevant earnings (ie. salary) is £12,000 (below the personal allowance) I can still contribute £2,880 to a pension refund that provides relief at source, increasing the contribution to £3,600 gross of 20%, even though relevant earnings are not subject to 20% tax, being below the personal allowance?

Hi,
You can see guidance here:
Tax on your private pension contributions
Thank you.