limiting user to "one per day" action?

I have Users claim a coupon and that action creates a new document under the Users Subcollection "Claimed_Coupons" (adds fields like coupon name, timestamp, category) and then another action also adds the User Reference in the "Claimed_by" field of the Coupon Document.

I'm now trying to limit the usage of the coupon, so that users can only claim it once per day.

Any suggestions how this can be done? The coupon has an expiry date (lasts one month).