For mashing, sweet potatoes need to be very tender, so you may want to set the time toward the longer end of the cooking range, depending on the size of your potatoes. Always choose potatoes that are the same size for even cooking.
From Time Inc’s “Instant Pot All-Time Best Recipes”
Place steam rack, with handles in the up position, in the inner pot of a 6-quart Instant Pot. Pour in 1 cup water. Place potatoes on rack.
Close and lock the lid of the Instant Pot. Turn the steam release handle to “Sealing” position. Cook on Steam setting at High Pressure 11 to 14 minutes or until tender when pierced with a fork. Open the cooker using Quick Pressure Release. Remove potatoes from cooker.
When cool enough to handle, peel potatoes and place in a large bowl. Mash roughly with a potato masher. Stir in butter, brown sugar, paprika and salt. Sprinkle with crumbled bacon, and serve immediately.