The way people write dates often confuses me, so I presume others will feel the same.
If you see a date written like this: 09/08/2021, what do you understand?
In Britain and in much of Europe we use the day/month/year format. So the above would mean 9 August 2021.
In the US, the month comes before the day, so it would mean 8 September 2021.
(To make matters worse, in Asia most countries use the year/month/day format!)
So instead of using numerals alone, I suggest you write out the month in words. That should avoid confusion.
And even if you still see it today, in modern writing we don’t use the abbreviations 1st, 2nd, 3rd and so on. But they are still spoken!
So I’m writing this post on 22 May 2021, but it will probably be posted on 1 June 2021.