annot.set_border() does not work properly

[djidos]

the annotation type is ink ( PDF_ANNOT_INK 15 )
I use annot.set_border(width=x.x) to change the width of the ink
I use pymupdf to check the width, it tells it is x.x now
but when I use acrobat to open the pdf file, the ink is still shown as the original width (in acrobat width is called thickness)
in acrobat->right click the ink->properties: it also tells that the thickness is x.x
but if I select the ink and drag to move it a little bit, the ink would be shown properly immediately
or if I change a little thickness in acrobat(e.g. in acrobat->right click the ink->properties->click up or down of the thickness), the ink would be shown properly immediately