Anyone had problems with using Allinson's bread flour for sourdough?

[BeerKilledMyPig]

I've been making sourdough for years, always used Allinson's strong white bread flour, but it suddenly won't work for me! I've tried making new starter several times, but it never even gets going. No changes to my method, environment, etc, everything is the same.

Anyone had similar happen to them? Any recommendations for a failsafe sourdough flour would be gratefully received!

Late reply, but yes!
I usually buy organic and got some Allinson (on offer) and had a couple of duff loaves. Got some extra strong Allinson flour and that seems to work ok. Have been using up the rubbish stuff feeding starter and flouring basket / surface etc.
I do think I get better results with organic