Unhappy customer

This thing that this shop cannot assist its very own customer to check payment due with a identity card or number is really depressing I went to their store lost my phone so I couldn't see how much I must pay so I went in while on duty having money to pay they said they can't access how much I owe without my store card what in the hell we are their customers they should change their system i felt less important to them at the end of the day we endup in debt cause of their system not being able to.view amount due with my id like hello I opened this account with my id shops like truworths we even buy without card but Identity card they must try fixing that