I'm sorry to be a killjoy but I have Dublin Bay and altough a good deep red colour flower, it is not a wonderfull climber. But I would also suggest that a climbing rose will use a lot of moisture and nutrients and would need to be gown in the ground or at a push, a very large pot.

I agree about where it needs to be planted, much bigger pot or ideally in the ground. they flower better if the stems are 'laid' as close to the horizontal as possible.

Thanks for the replies. I only bought it last year, I’ll probably repot in in the autumn.
It wasn’t the care of the rose I was needing help with so much as to how to train it.

the stems need training as close to the horizontal as they will bend. Tie them in loosely with a soft twine so they don't crush/damage the stems.

I have this rose and this year it has rambled well. I think you have to be patient. I have pruned mine sparingly this year.