Alt and loop combined fragment operands all over the place

In some sequence diagrams I am making, I have a few alt and/or loop combined fragments, but for some reason the Operand labels that show up on the diagram are always in a weird position and it won’t let me place them where I want. Using sweeper or magnet moves them, but messes up their positioning. Trying to ‘undo’ those operations doesn’t fix their position. Any idea why this could be happening and how to get around it?