Hi KuenHK,
Your parents would each have to contact our webchat facility in their own right and pass security to progress chase their forms.
We cannot advise how long it may take to process the form.
They can contact the webchat team at:
Self Assessment: general enquiries
From 4 September, the Self Assessment telephone number opens again.
They could call 0300 200 3310 to progress chase their UTR's.
Thank you.