Hi Dobbin, that is every gardeners worst nightmare. I’m glad to hear you have managed to turn the situation around and fair play to you for sticking to it.
I personally only use my own garden compost and horse manure from a local racing stable(makes the plants grow faster!!).
I would advise anyone to devote as much space as is practicable to the production of your own compost in order to minimise what needs to be bought in. And when buying manure go directly to the source to see whats actually used and how its being stored etc.
Don.