If a player dies whilst welded to a part with a WeldConstraint which is parented to the part, trying to re-weld to the same part after respawning results in death.
Here is a reproduction file. Activating the ProximityPrompt welds your character to the part. Upon resetting, when you try to activate the prompt again your character will be killed.
Hello and thank you for your patience and reaching out. Our team is currently investigating the issue, thank you for the repro file it has been very helpful.
If you are interested in a work around while we investigate, if you use LowerTorso instead of Parimary then it seems to work as expected.
This behaviour is still very much present (using Weld, not WeldConstraint, but I’m told they function the same). I tried the workaround but the issue persists.