Ran into this problem in the Goblin camp / Desecrated Temple of Selune and I have no idea why since I've been here many times with 1.3 without this problem. However, this time, no matter how many times I tried, a version of this happened. I managed to eventually get to the portal by entering from the area closest to the temple entrance where I was above ground enough to reach it - entering from the furthest area had just my head and shoulders sticking up from the ground. Once I had it, I was able to fast travel to where I already was and that resolved any issue for the time being.

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