This grower is sure of this plant identification.
plant in 7cm pot
Navelwort, Wall pennywort, Pennywort
Umbilicus rupestris (Navelwort). This species has round navel-like leaves and pallid greeny cream spikes of bell-shaped flowers. It grows on shady walls, trees and damp rock crevices as a wild flower in southern & western Europe.
Happy to swap any of the plants on my listings for unusual alpines, perennials, Galanthus, and rare small tender succulents.