How to get rid of a vba message

I use the following code to put the headings on a group of 12 monthly management accounts

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My problem concerns the numbered lines. MonthAr is an array containing the 12 month names, and the purpose of the code is to place these names in 12 defined ranges on the sheet.The code does this OK, the problem is that on each iteration of the code I get a message saying "There's already data here do you want to continue ?" 12 times. The message is not an error message so I don't know how to avoid it specially so because there is no data in those cells.
How do I prevent it showin?

Thanks very much for that it works perfectly. A nice little object to Know.
John