Gradient export problem?

Good morning community!

I have been using Adobe for many years and I have a problem to export the gradient effect.

I don't know if I'm doing something wrong or there is some new setting.
I see a gradient effect on the monitor, but then when I want to export the file to PNG or JPEG, this gradient disappears from the image.

I usually export to PNG and JPEG, but the result does not change.

Especially when I go to decrease the percentage of the file.