Pathetic they ruined my credit score

They ruined my credit score they never captured the debit order date I made an arrangement for them to debit 25th and they did not capture the payment date the debit order never went through and they called me I was shocked as I thought they debited they checked the discovered the never captured the date at all I am disputing this missed payment is was not my fault and it is now reflecting bad on my credit score I can not apply for any finance due to that 1 missed payment that reflects bad on my credit pathedic