First: lovely present for your sister and the embroidery looks immaculate <3 But I fear my English knowledge just left the room ...
‘ Are used my magnetic hoop and then floated the towel on top of the hoop. I was able to secure the towel on top of the hoop without adding re-positioning adhesive spray. I also added water soluble stabilizer on top of the towel to prevent the stitches from sinking into the nap of the towel.’
I have no clue what you did. I think I have neither enough knowledge about machine embroidery nor is my English vocabulary sufficient... But I will research :-9