I am not aware of any reports of immediate-type hypersensitivity reactions like hives to fillers. It is unlikely that this is related and even possible that these are not hives but something else -- for example, sweat bumps.
If you were to have an allergy to filler it would be immediate and also in the area injected. What you are experiencing is a rash or uticaria from something else. It's not related to the filler.
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