Caffeine is found in tea from the tea plant, for example in green and black tea. Herbal teas made from other plants, by contrast, are naturally caffeine free. Tea from olive leaves is one of them.
Our Ölich Olive Leaf Tea, Immunliebe and Schlafliebe are caffeine free. Kraftliebe contains green tea as well as olive leaves, and therefore natural caffeine. If you want to avoid caffeine completely, choose one of the other three.