Yes. If you don’t intend to use that same device as your current mobile phone.
You can usually add old mobile phone bills debt to your list of creditors, but if you want to add this to your Trust Deed or Debt Arrangement Scheme, you need to ensure that the contract has already been canceled and expect that any early cancelation fees will also be added to your debt with the provider and will increase your total level of debt.  You cannot add mobile phone arrears to the plan and expect to be able to still use the device(s).
The same provider is then unlikely to offer you a new contract while in your Trust Deed.