Actually, may I ask @clint1 what model of pen that is?
If it’s a ‘LeGrand’ from the ‘Around the World in 80 days’ series, Montblanc’s website currently only lists nib options of ‘M’ or ‘F’ - there is no ‘EF’ option listed!
In which case I would suggest that your nib may be an ‘F’ (nominal width 0.5mm), rather than a ‘M’ (nominal width 0.62mm).
And, if I were you, if you think that your pen writes with too-broad a line, I would go back to the store where you bought it, and suggest to the Manager that his sales staff need to be trained on the details of the products that they are selling!
To be fair, that model is listed as sold out online, and it is possible that some stores may still have older stock of the ‘Around the World’ LeGrand pen, which may in fact have come with ‘EF’ nibs.
One way to check this would be to take your pen back to the store, and to dip-test it in comparison with some ‘LeGrand’ pens from the standard ranges with ‘EF’, ‘F’, and ‘M’ nibs.
All of the LeGrand pens are meant to have nib grades of the same widths.
I.e. a standard LeGrand’s ‘EF’ nib should be the same width as the nib on an ‘Around the World in 80 Days’ LeGrand that has an ‘EF’ nib on it. And the ‘F’ nibs should be the same, the ‘M’ nibs should match, etc.