Need more info - how long have you had the plants? Were they outside in their pots all winter? Are the two which are not doing well in more sun or wind than the others? What variety of Acer are they?

I have uploaded 2 photos I hope you can see them, they have been in pots for a few years and were left out in winter as in previous years I think they are dead there is just branches now no leaves

I dont know how to add photos but I have only got them 2 under my photos

I've had a look at the pics - unfortunately, you appear to have posted pictures of very healthy ones - it was the stick ones I wanted to see. However, if they've been in the same pots (the unhealthy ones) for more than 2 years, its possible they were potbound, when it would be next to impossible for them to have enough water without your doing it twice a day, or even got frozen in winter and damage occurred to the roots.

Sorry, these were the plants last year and they are just twigs this year, I wondered if I repot them do you think its worth while seeing if they come back.

Scrape back a little bark on the central stems with your fingernail - if the wood underneath is brown and dry, they're dead - if its moist and greenish, then worth trying repotting - but also have a look at the rootballs too - if you have lots of healthy roots and they're completely choked and crowded, and the scrape test shows they're alive, definitely worth doing.

Thanks Bamboo for all your help, they are dead, the winter was severe here, just a shame they were good healthy plants I will be bringing the others indoors this year again thanks for your help.