SEP IRA contributions

I have a question about SEP IRA contributions. I am self-employed (sole prop) and I have a couple of IRA's, one of which is a SEP. Each year I mail a check for whatever I want to contribute to the account for that year to the bank  holding my SEP. This year I got a Form 5498 from them, with the SEP box checked, showing the contribution I made in 2023, let's say it is $2,000.00.  When I am doing my taxes and TT asks if I have made a SEP contribution, do I enter that $2,000.00 from the form, or do I enter a different amount if I want to contribute now (and send then a check for that amount)?

 

OR - if I put the $2,000 into TT, do I mail my bank a check for $2,000? 

 

In other words, the Form 5498 that I got (which shows 2023 as the year) - is that for my 2022 contribution? I've always done my own taxes and have been self-employed since 1999, and never thought to ask this before. TIA.