Is it okay to apply sunscreen only once a day?

The product I am using is the Mediheal Madecassoside Sun Serum.

The product detail page said it lasts for 24 hours.

In fact, if you apply makeup after applying sunscreen, you need to apply sunscreen on top frequently throughout the day.

It's actually difficult to apply it properly, you know? ㅠㅠ So I'm just going to use this one product.

I apply it in the morning before going to work and I don't apply any extra.

Since good sunscreens are coming out these days, it should be okay not to reapply it in the middle of the day, right..?

Actually, ultraviolet rays require prolonged exposure to the outside.

Since I work indoors almost all the time except for commuting... I think it might be okay.

I'm worried because the UV rays are so strong.