Run Time Error 5844

[HTSCF Fareha]

I've occasionally been getting this error when running a macro enabled template.

Error.jpg

It doesn't happen every time, but when it does, it occurs on this line of code as shown in bold.

For Each oCC In ActiveDocument.ContentControls
    Set oRng = oCC.Range
    Select Case oCC.Title
        Case "One"
            oRng.Text = .TextBox1.Text
        Case "Two"
            oRng.Text = .TextBox2.Text
        Case "Three"
            oRng.Text = .ComboBox1.Value
            oRng.Font.Color = .ComboBox1.BackColor
        Case "Four"
            oRng.Text = .TextBox4.Text
.......

The only thing that I can add that might help in solving this issue, is that text is pasted into TextBox4, after being copied from another bespoke source, prior to pressing the proverbial "Enter" button to commit the TextBox / ComboBox entries to the word document.

The only thing that I have found online seems to reference carriage returns which might have something to do with this?
https://social.msdn.microsoft.com/Forums/en-US/a6e801ca-2d12-4a66-8df4-734f15cf4333/linebreak-in-contentcontrol?forum=innovateonoffice

Unfortunately I cannot provide any copy examples of the text that is causing the issue because this was work based.

I don't know if there is something codewise that can be done to alleviate the error?

Many thanks!
Steve