What would my creditors & debt management company do if i missed 1 of my monthly payments??

I am currently on a debt management plan with a third party company whom i pay £300 per month towards clearing my debts. This £300 gets split to pay off my creditors.. Just out of interest what would my creditors/debt management company do if i was to miss one of these monthly payments? What would the consequences be if i were to miss a payment?