Try talking to a lawyer. Seriously.
It depends on your state, the terms of the easement, how the easement was created, and use of the easement since it was created.
For example, here in Texas, you can have an express easement (generally created by an instrument in writing), an implied easement or easement by necessity (which can be created if the property was subdivided from another property that needs to cross your property to get to the road), or an easement by use or adverse possession (which can be created by trespassing over someone else’s land for a sufficient number of years). Each has its own rights.
You can also change the rights under an easement by how it is used. For example, you could have an express easement that is 50 feet wide and if the owner of the land puts up a fence with a 25 foot wide gate and you don’t object then the land owner could basically cut 25 feet off of the width of your easement by adverse possession.
It is a very complicated question which is why you can’t find a simple answer on the interweb.
Too early for a lawyer. We need more facts. Sometimes Town Laws change and it can’t go back where it was.