It has two tops, and then higher again two tops. It's not really a double trunk.
I think you can remove one of the upper two tops now - the left one. I'd also remove that branch that is growing upwards on the branch on the right.
I would remove the left top (the most damaged one). I probably would not do that now though, but I'd first repot it (when it's the time for repotting), next let it get stronger and grow more foliage.
Next you can start building it up again.
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