The timber fascia needs to have a building material that is stronger than the gutter and fascia building materials.
Or you could try moving the reference line position of the fascia to the gutter side.
Or manually trim the gutter fascia so it doesn't overlap (select in plan and CTRL click on the inside edge of the fascia).
Or place them in different layers and ensure they have different intersection priority numbers.
One of the forum moderators.
Versions 6.5 to 25
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