Make adjustment stay, before applying a preset. Reset, will turn my photo to my adjusted settings.

keep unadjusted version:
first make your adjustments. Then make a virtual copy (which includes a copy of the same adjustments). Then apply your preset to only one of these.

why is the preset removing your adjustments?

The idea of a preset, is that it can override just particular adjustments of interest, while leaving everything else alone.

So the job of a preset, IS to make changes to an image. But it sounds as if your preset is overriding everything - it is not selective enough.

When you make a new preset, there is a dialog where all the different kinds of LR adjustment are presented, each with a checkbox.

These checkboxes define the scope of the preset - they say what is it FOR.

• You can first apply the preset to an image,
• and then right-click on the preset and select 'Update from Current Image with Current Settings'.
• You will see again, the same dialog that would have been seen when the preset was first made.
• Uncheck within this dialog, all the different types of adjustment, that you do NOT want this preset to override with new values.
• Then Update the preset with this new, reduced scope.

Say (for example) the intention behind a preset was just to add a particular "look" with Split Toning and Vignette, and do nothing else. Those should be the only options checked. When applied to an image, everything BUT Split Toning and Vignette would then be left in place, just as before.

Incidentally: if you want to undo the effect of a preset, and go back to the previous adjustments, you can step back in the History. You don't need to Reset the image, and you definitely do not need to re-import it!