UC ERROR

At 4:14am I received a message in my journal which states I will no longer receive payments for my son, it explains that the reason is because I didn't not complete a task in my To-do but I have never received any task requesting me to update education information. The only messages I have received have been in my journal
30th Jan 2025 ‘You told us your son is enrolled or accepted on a full-time education or training course. If this is still correct, you do not need to contact us. If this has changed, you must report a change (opens in new tab)

And

15th May 2025 ‘You told us your son is in full-time education or training, like A-levels or a similar course. We need to make sure your Universal Credit payments for your child are still correct. You do not need to contact us if your child is still in full-time education or training.

I rang UC and explained that I have never received a To-Do task requesting me to update my sons education. The agent could not confirm or provide a date of when this task was meant to have been sent to me. He explained that he will pass it on for a case manager to look in to it. A couple of minutes after the call a couple of messages were added to my journal
‘Children and other people who live with you - declare changes cancelled‘
‘ After speaking today, I've asked that a case manager looks at your case and responds to the questions you raised. They will respond by 2 September 2025, before 6:00pm.’

Before calling them I did submit a message in journal, explaining the same thing as I told them on the phone and mentioned that the only messages I had received (listed above/regarding child's education, if still same then no need to contact them) and that I received them in Jan 2025 and May 2025. A couple hours later, I received another message in my journal
‘ Hello Thank you for your messages and call to the helpline. The messages you have received are automated messages issued by the UC system. (I'm assuming she's talking about the messages from Jan & May)
However, to ensure you are paid the correct money for your children, just update the education details for your child on your claim:
- click on 'report a change' tab
- click on 'children who live with you'
- click on 'make a change'
- select child's name and tick the option they are in 'further education'
- date of change is from when they continued in college
Regards Yvonne, UC

My questions are If UC have said my child's payment will stop, for an error they have made regarding my child's education due to falsely assuming I failed to complete a To-do task, a task that they never sent me, Are they correct in advising me to update his education via a change of circumstances to avoid the risk of losing payment? even though no change has occurred in his education?
The agent's advice seems unfair and incorrect (or am I wrong?)
If I was to follow this advice, would this put my transitional protection at risk? It makes no sense, that I need to report a change that hasn't occurred, this issue seems to be an error on their part. This has really overwhelmed me with worry and put my anxiety through the roof, especially since my next payment is due in 7 days for the assessment period 2 August to 1 September 2025

What should I do?