Downgrade my plan
Downgrade your plan if you want fewer features, or if you don't want to pay for features that you don't think you'll use. You can upgrade in the future, but you'll have to reconstruct any features you lost in downgrading.
For example, if you have the Commerce plan and have added products, once you downgrade your plan all of your shop work will be deleted.
You'll need to contact support to do this.