Not receiving any notifications about late payment penalties

I'm not getting any letter or email from HMRC about penalties I've been getting. I just found out today by going on to the HMRC app that I have 3 new penalties waiting to be paid. I've only started using the app in the last few months after finding out I had penalties from several years ago which again I had no notification about, and had to pay over £4,000 to cover the fines and all of interest added on in that time. I checked the app and my email address is correct in the paperless settings section. Why am I not receiving any mails about these penalties?

Hi,
We would need to review your record to check this for you.
You can contact HMRC at:
Self Assessment: general enquiries
Thank you.