Self Assessment for Child benefit form help

I have to do a tax return for last tax year 23-24 as I just tipped over the 50k mark. We haven’t done one for the last few years as have been under but have done one before in the past when I was made redundant. They were informed that we didn’t need to in the intervening years. It says to enter the latest out of - Tax year end date your income for Child Benefit purposes went over £50k OR Date your child benefit started (if after 2013) OR 7th January 2013 (if you or your partner got child benefit before the new rules became effective) Out of the three options the top one is the latest (5/4/2024) But where do we enter it? There’s three boxes Top one says Date Child Benefit payments *started* It’s not the middle one as that’s to do with capital gains and I tried the bottom one even though it says from and have had the whole thing rejected as an incomplete form. What are they wanting and where? It should be such a simple form but they’ve managed to complicate it for no reason, The helpline directs me to videos that don’t mention it and the website sends me around in circles with nothing about this as far as I can see. Any advice, please?

Hi,
To give you the right advice here, we may need to confirm some elements of your query, and access your record.
Please therefor contact us by webchat or phone via Self Assessment: general enquiries to allow us to do this.
Thank you.