Click the trash icon at the end of the row and confirm "Are you sure you want to delete this item?". The row is removed and a Delete entry (old price → $0.00) is written to the Price Change Log.

Subscriptions that were pinned to that exact row are not cancelled: Sprwt unlinks them from the deleted row so that, at renewal, they fall back to looking up a price on the same plan with the same days-per-week and meals-per-day. If no such row exists any more, the Current Subscriptions table shows "Impossible to renew! No Price found." for them and the automatic renewal cannot run — re-create a matching price or move those customers to another plan.