This is a thornless rose, very lax habit, very prolific purplish flowers and flowers for many weeks. Any idea what it is please?

Does it get bottle shaped hips? If so it might be rosa pendulina.

But the flowers look more like the rambler Veilchenblau, could it just be laying down, rather than climbing up?

Thanks Thelma! I think its the Veilchenblau
It has nothing to climb up as its against a cliff face, so goes so high then flops over. It was in the garden when I came here and always has lots of compliments. I'm not a rose lover but the thornless bit is very endearing. Thank you for giving it a name, even if I can't pronounce it!