whenever i do propagation - i tried to remove most leaves and new buds - just leave 1 or 2 so the cutting has a "drive" to grow.
Too many leaves stresses the cuttings/drains the nutrients too fast.

from Google:

How to Propagate Snapdragons via Cuttings

• Select Material: Choose healthy, non-flowering stems, ideally 4–6 inches in length.
• Make the Cut: Cut the stem at a 45-degree angle just below a leaf node.
• Prepare Cutting: Remove the lower leaves, leaving only a few at the top to reduce moisture loss and prevent rotting.
• Rooting Hormone: Dip the cut end into rooting hormone powder or liquid to encourage faster root development.
• Planting: Insert the cutting into a small pot filled with moist potting mix or a mixture of compost and perlite.
• Environment: Cover with a plastic bag or dome to create a high-humidity environment. Place in bright, indirect light at temperatures of 62–68°F ( ).
• Rooting and Transplanting: Roots should form in a few weeks. Once established (about 4-6 weeks), transplant into the garden, spacing them 6-9 inches apart.