Hello Kate and welcome to the Forum
Just to explain what may be affecting your search as the problem that is still facing many puppy seekers is that the most reputable breeders have been reluctant to have litters while the country is still affected by restrictions due to the pandemic. The worst breeders and puppy farmers have been cashing in by supplying puppies in poor health and of dubious parentage in the interim and shelters and re-homing centres are now flooded with ‘lockdown puppies’ whose behaviour issues, poor health or just people beginning to go back to work have led to them being abandoned.
The best breeders almost always have waiting lists for their puppies and due to the pandemic many have given up adding new names to the list. Black miniature schnauzers are in the minority in any event as compared to pepper & salt so puppies will be even harder to source from a reputable breeder.
Breeders of black miniature schnauzers only will not be identified on the Kennel Club website but your starting point should be to check out the Assured Breeder lists and contact as many as you can to see if they are planning a litter in the future and, if you are happy with their replies to your questions on all areas of concern regarding the raising of the pups, try to arrange to meet them and their dogs at a suitable venue if not at their home. This is a major stumbling block to puppy seekers finding a good breeder as the face to face contact on both sides is so important and has been pretty much impossible for the past year.
You could also try contacting the breed clubs for any recommendations although you must check the breeders yourself fully and not just rely on a recommendation. Even if the breeder you contact does not breed black minis they may be able to give you the name of a breeder who does. If you look through the Puppy Section and Breeding Section on this Forum you will find several topics with advice and information on how to source a well bred puppy and what to look for in a breeder.
Introducing a new puppy to your family is a commitment for many years and needs patience to find a good breeder you can trust. It is sad the impact that the pandemic has had both on puppy seekers and the best breeders but don’t compromise and go for an advertised puppy online or a recommendation you are not fully confident with as it really is worth waiting to get a fit, healthy puppy who will have a long happy life with you in the years to come.
https://www.thekennelclub.org.uk/search ... rest=False
http://www.theminiatureschnauzerclub.co.uk/