If you have two seperate forms then look at the number of shares...

If you have two seperate forms then look at the number of shares on each form.
That is the amount you are accepting on each form.
They can not increase or reduce this number.

If you want to sell less, cross out any numbers, written or printed and put in the number you want to sell.
Sign all changes.

Then send back.
It will be up to MIN if they want to accept the amount you write on the acceptance form.
If they don't accept your amended number then the amount will be zero.

This is straight forward contract law.
They make an offer - you counter off.
If they don't accept then there is no contract and no sale.

Nothing stops anyone from changing the amount of shares and signing the changes on the form regardless of what MIN put in their Offer.

My opinions only - DYOR - Get your own advice