Sounds like you have a blueprint circular dependency, which is super fun because UE4 doesn’t tell you that its a thing until its too late to know why or where.
We’ve had this countless times where the editor seems to get stuck at either 71 or 72% while loading, only way to fix is to revert work you’ve done recently until it loads again. Thats if you’re using source control anyway, if not and this is the issue then your next best option is to just delete assets until it works to find the offending asset and remake it.