Is it outside, if so when did you move it out? I suspect it may be this year's weather.

Can yougive it a high potash feed and a bit of warmth such as a gh or warm windowsill to try to get it going again.
I left some geranium cuttings in the gh and they areflowering.....all round the edge of the pot......

Thank you both,for your comments..It has been outside since about mid June,Sarracenic..it gets sun (when there is any) from mid afternoon onwards..and is quite sheltered by the house wall...and Pam,the pot had all new compost in it,but only been fed a couple of times since...been too wet to liquid feed..I had them growing in pots in the back garden last year...much sunnier for longer there..would you recommend I move them back ?

They do like it warm and sunny (fat-chance for most of this year).

I think that the warmth would help for a bit, hopefully just until the flowers begin to open,
I have some ordinary geraniums that at the end of lat year I stuffed altogether in a big pot in the cold gh, they amazed me by flowering most of the winter (as did osteospermum)
I put them in a sunny sheltered spotand they're still going strong.....I get the feeling that they need the heat to start the flowerbuds then they cope...I could be quite wrong but it may be worth a try

Thanks,I will do that..and hope the sun shines again soon..thick cloud again here today..but still warm..My Pelargoniums have only really put a spurt on this past week ..and all the Fuchsias too...so they might get going at some point !