Yes, we have a 30-day touch timer for all structures, and your player (or a friend) must physically touch your structure to reset it. If you don’t, it’ll be automatically deleted
If you know you’ll be gone for a while, you can ask someone else to touch your structures for you. You can also make use of our Keep Structures (Holiday) supporter package in https://support.hws.global which lets you save structures indefinitely within a season.
I just checked, and you didn’t touch your structures since October. As an exception I restored them now.