iCloud not deleting old messages

Hey WhyCantILogInAgainWithMyOldNam,

It appears that you're having a problem with deleting Messages from your devices. Your iCloud storage is full, so you've been clearing out Messages since you're using Messages in iCloud. The problem is, after clearing out messages and threads, you're not seeing any difference in your iCloud storage. We wouldn’t want to have to pay extra money for additional iCloud storage either, and we're glad to provide assistance.

First, log into iCloud.com and select “Account Settings”. In the Storage section, is the amount of storage taken up by Messages the same as your devices? If it’s different, restart all of your devices and check the iCloud storage on each (Settings > [your name] > iCloud > Manage Storage for an iOS/iPadOS device and System Preferences > iCloud > Manage for macOS).

Use Messages in iCloud - Apple Support -- If that didn’t resolve the issue, we need for you to check a few things for us. Please reply back with each device you're using and the operating system it's currently on. Then, provide the answer to the following questions under each device listed:

1. Is the list of messages on all 3 devices the same?
2. If you delete a thread on one device, is the thread deleted on the other two devices? 
3. If you check iCloud storage on all devices, are they all showing the same amount being taken up in iCloud / Messages?

Once we have the answers, we'll know better how to help.

All the best.

Thanks for getting back to us and tygb regarding this issue. It’s appreciated.

Have you had a chance to have a look at Manage your iCloud storage - Apple Support yet? As tygb said, your Messages aren't visible at iCloud.com.

Since all of your devices are in agreement with how much storage space is being used by iCloud Messages, using a browser on your Mac, sign into iCloud.com and select Account Settings. How much storage space is shown being used there? If it agrees with how much Messages storage is being used on your devices, which category is using the most?

Let us know how that goes.

Take care.

I am interrupting the chat .

Click on finder > take cursor on top menu bar > Go > keep on holding option key and click on library .

Find a folder messages > move three fingers towards right on the track pad you will find Archive , here you will find the messages data , also in attachment .

Double click on the chat to open , or right click on it and click open .

Deleting this data is to be done when apple support senior care advisors recommends you Contact Apple for support and service - Apple Support

The old chats are occupying Macintosh HD space .

You can also click on apple logo > about this Mac > storage > manage > under recommendations in the side bar window if you see any messages .

Then click on review files > again select messages in side bar > large files > select them and click on delete .

Click on drop down arrow to see the size of messages .

This screen shot is just for an illustration , in fact in my Mac no messages are saved that's the reason they are showing empty .

Note : if you consult apple support advisors request them to refresh iCloud account data from their server end .

Did you contacted apple care senior care advisors ? take suggestions from them see the article Use Messages in iCloud on Mac - Apple Support

For the time being create new admin account in Mac Set up users, guests and groups on Mac - Apple Support

The web refreshing of account is done by the advisors , I am not sure if Mac is corrupted or other devices synced .

Take back of the data , may be you have to erase iPhone / Mac and reinstall them , first take advice from apple support .

I doubt they know how,

I had an issue with other documents and that was not deleted , they refreshed the account and data was reduced .

Contact senior apple care advisors .

You can downgrade the storage plan .

As you mentioned -

When I delete a message or a message thread, it does NOT affect the icloud storage.

Messages icon is not visible when you sign in at www.icloud.com and it never occupies space in iCloud , the other applications that are synced like notes, calendars , mails , photos ..... occupy iCloud storage space Turn iCloud features on or off - Apple Support

Yes when you delete messages from any device synced with others the conversations are deleted Delete messages on iPhone - Apple Support

How to delete messages in iCloud - Apple Support

It will never decrease the iCloud storage space or affect it .

It depends upon the user to upgrade or downgrade the storage plan Upgrade or downgrade your iCloud storage - Apple Support

Or follow other methods to reduce the data .

Manage your iCloud storage - Apple Support

Save space on your MacBook Air - Apple Support

How to free up storage space on your Mac - Apple Support

Find and delete files on your Mac - Apple Support

If iCloud is not deleting messages from Mac Change General preferences in Messages on Mac - Apple Support

You had a case id created by them , wait for call they might be consulting with their engineering team ( if required complete sys diagnostics report or log details might be required to solve the problem ) .