[bug]: watchtower sessions are not reused after deactivation/activation

Background

During testing I deactivated (NOT REMOVED) a watchtower and activated it again (with AddWatchtower). Everytime I do so, three new Sessions are added. One for each type.

Your environment

version of lnd 0.18.0
which operating system (uname -a on *Nix) umbrel
version of btcd, bitcoind, or other backend
any other relevant environment details

Steps to reproduce

This is how I did it. It can probably be done without an Umbrel

Run lnd on an umbrel, with watchtower client & watchtower service activated.
Add the own watchtower as watchtower to the service using the AddWatchtower api endpoint.
3 Sessions are created
Deactivate the watchtower using the DeactivateTower api endpoint.
Activate the watchtower again by using AddWatchtower api endpoint again.
Wait a few seconds... 3 new Sessions are created.

Expected behaviour

As I understood it in contrary to RemoveWatchtower, deactvating and adding a watchtower should continue to use the already established sessions instead of discarding them an creating new ones. If it does not, then I do not see the difference between RemoveWatchtower and DeactivateWatchtower.

Actual behaviour

It creates new Sessions each time.

lightningnetwork / lnd