Dropped the ball
Use them loads, products fine and prices on a par with other stationery suppliers. All of sudden they now reject cash back, last 8 transactions rejected. Thankfully other suppliers are available on quid co for stationery. Rymans have lost £400 per month, but someone else now gains.
Update 10.11.16. That's the 9th transaction now rejected, would love a reason for the rejected transactions.