Excel slows and grows larger with every use of VBA.

I'm currently working on a spreadsheet that is designed so that the user can not alter any data without using a UserForm that automatically time, name and reason stamps the changes.
In order to do this I created a UserForm that copies the entry that needs to be changed into a hidden spreadsheet and makes the changes before copying it back to the master sheet. The code does initially work, however, the problem is every time I use the userform, excel gets slower and increases in size until it becomes unusable. (The size and speed stay as they are despite saving, closing and reopening) I originally thought it could be a clipboard issue due to the copying and pasting but added in code to wipe the clipboard after every paste event, although this doesn't explain why the speed remains slow even after the programme is reopened. I've checked the end cells and they are correctly at the end of my used range. I also stopped auto calculations and all that good stuff but to no avail.
Unfortunately I am on a workplace computer and do not have access rights to see if its a third party programme causing it, although I don't understand how it would effect the size of the spreadsheet if it was.

All userforms which have this problem share a similar code but it seems to be the following which is the problem. (Though I seem to have successfully used it on another spreadsheet)

The copy to the hidden sheet:

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Or the copy back to the master sheet:

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Sorry, yes the A is a typo, whilst typing the code in on here.
The entire range does not need to be selected just columns A:L, however, I'm a newbie at VBA and wouldn't know how to just select that range.

Although your code does work, the problem still persists. The spread sheet grows significantly in size and time taken to complete the macro the more it is used.
The spread sheet has grown from 478KB to 1.42MB from simply using the macro 4 times.
All the macro does is copy the entry to a hidden sheet, amend some of the data and copy it back over.

Ok so the process is split into 3 parts.
The user needs to first identify the entry that they need to view which is:

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After that, the data review page will appear where users can view the data and make minor amendments if needed:

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From there, any amendments made will need to authorised by entering your name:

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