Giant retail brands Debenhams and Topshop could close for good leaving customers in the dark about getting their money back from vouchers or refunds.

Sir Philip Green’s Arcadia fell into administration on Monday evening threatening the Topshop, Topman, Dorothy Perkins, Burton and Miss Selfridge brands. Meanwhile, high-street favourite Debenhams has entered liquidation after its was unable to find a buyer.

The day after the store announced its closures, the website was overwhelmed by customers searching for a bargain. This led to a sharp rise in online traffic and consequently caused long virtual queues which thousands of shoppers joined by the morning of December 2.

In response to the “unprecedented” volume of visitors, a spokesman for the chain shared that they were forced to introduce the queuing system, but they would get “onto the site as soon as possible."

For those who have vouchers or gift cards, you are not guaranteed to get your money back as a company can refuse to honour these once it has gone into administration.

This is because administrators view customers with vouchers and gift cards as "creditors": people who are owed money by the businesses. Voucher holders will have to get in line with other creditors and customers tend to be at the back of the queue behind the taxman, banks and suppliers.

If you have already bought goods and need to return them, you should do this while the stores are trading otherwise the situation becomes more complicated.

Will stores stay open?

Debenhams has confirmed it will continue to trade through its 124 British stores and online to clear its stock. Once it has all been sold, all operations will close if the brand is still unable to find a buyer.

As for Arcadia brands, stores will continue to trade while insolvency consultants seek a buyer for all or some of the big names.

What should I do if I need to return an item?

If you have bought a piece of clothing or an item that either does not fit or is broken you should go to a store as soon as possible. If you are within your rights, the company should offer a refund.

A spokesman at Debenhams said the group is still currently accepting orders and processing refunds and returns as normal. He said: "We continue to accept credit cards, store cards, gift cards and beauty club rewards as forms of payment.”

However, if you have any trouble getting a refund you may need to write to the company. Martyn James, of consumer service Resolver, said it is important to write to the company or contact them on Twitter to make your intentions clear that you will need a refund and are planning to return an item.

If you have written proof that you do not want the item and the clothing store fails to refund you, you can then contact your bank. Mr James said: “I would expect the bank to give a refund on these grounds but you should get onto it right away to get these goods returned.”

It has become increasingly popular to buy several sizes of one item via buy now pay later schemes and return those that do not fit. If you done this, Mr James said it is clear that you did not intend to keep all of those you can contact the third party pay scheme if you are unable to get a refund from the store.

How do I get a refund on my voucher?

When a company has entered administration an insolvency practitioner is appointed to organise and repay its debts.

You can make a claim by writing to the administrator detailing how much money you are owed and what it was for.

Any cash left will first go towards paying the secured creditors and employees, the rest will then be split between everyone who has submitted a claim.

The next step is to ask your credit card provider for a refund under Section 75 of the Consumer Credit Act. The section is a legal act that protects you when you spend on your credit card but the value of the item must be between £100 and £30,000.

If you bought the item with a debit card you may be able to make a claim using the Chargeback scheme. This gives people a chance of getting their money back from their bank but only if a service has not been provided.

Those who are seeking to return clothes will not be able to claim as they received the goods they paid for.

Is there a chance online orders may never arrive?

Customers may find that an online order placed will now not be shipped, Mr James said. However, operations are likely to continue while negotiations are underway within the business.

Arcadia brands have confirmed that online orders made over the Black Friday sales weekend will be delivered.

But if your order does not arrive, there are still ways to get your money back. You cancel most items that you buy online, including clothes, with a 14-day window from when the order was made, according to a rule called the consumer contract regulation.