sangel... customs a issue ...I had no idea. Can you order from Holland? Or many nurseries in the US have them but don't know if they ship to Israel. Holland is where the US had imported most of the amaryllis bulbs until the US nurseries have started to grow them. They are big business especially during the Holidays. I force many here in my zone during Xmas in pots in a sunny window. It's to cold to grow the hybrids outside in my zone. Florida is a warmer zone on the east coast.
The no blooms issue.. it took a few years for the Belladonna Lily's to bloom out in my garden. 3-4 years. And all my belladonna's naturalized in the garden always have leaves with the flowers. So doesn't live up to the naked lady moniker. Since yours are not flowering you can always do what I do, threaten them if they don't flower then you'll put them out.
Actually if they are planted to deep or don't have enough stored energy or matured enough will take longer to flower. Other than that I don't know what to suggest, assuming they are in at least 7-8 hours of sun a day. . Maybe start a separate thread asking why belladonnas don't flower, and some one will help out. Have you tried bulb food ? It's early spring here and all the belladonna leaves have sprouted out. They won't flower til august here.
Keeping 🤞the bulbs flower for you next season.
