Those seeds should germinate fairly easily. Keep moist until germination starts. Keep the seed at 68-70°F. Sow around ¼ inch deep. Seed should begin germinating in 10-20 days.
If you've done all this, it could be either that you have poor seed or that the seeds dried out during the germination period.
If you haven't already, I'd sow them in a mixture of 50/50 compost/vermiculite (which keeps moisture in), and enclose the pot inside a plastic bag. They also like light to grow rather than being in the dark.
I'm assuming your seed is bought rather than collected as there are some Hib.Syriacus hybrids which don't produce viable seed.

Thanks Bertie,

I will give it a go.

Paul