Problem using for loop

clear all;clc;

% load OSI_SAF_OSI401_10km_geoloc_area.mat

% path to data directory
folderpath = 'C:\Users\SK\Documents\MATLAB\SIC_data\OSISAF_401b\';

for m = 7:9;
    if m==7
        datapath = '2007\07\';
    elseif m==8
        datapath = '2007\08\';
    elseif m==9
        datapath = '2007\09\';
    end
    % make list of files in selected folder
    files = dir( fullfile(folderpath,datapath,'ice_conc_nh_2*.hdf') );
    files = {files.name}';
    %
    dd = [];
    %
    % go through all files and add into datamatrix dcube
    for ii=1:numel(files)
        %
        disp(files{ii}); % show filename on screen to follow progress
        filename = fullfile(folderpath,datapath,files{ii}); % full path to file
        %
        d = h5read(filename,'/Data/data[00]'); % read data
        h = h5read(filename,'/Header'); % read header with d/m/y information
        %
        d = reshape(d,760,1120);
        d(d==-99)=NaN;
        d(d<0)=NaN;
        %
        dd(:,:,ii) = d;
    end
    sic_mnth(:,:,3) = nanmean(dd,3);
    % if i put m instead i get the result but i don't want the 
    % sic_mnth to be (:,:,9) size
end
%
load lat_long.mat;
figure(200707);
clf; hold on;
m_proj('stereographic','lat',90,'long',0,'radius',33);
% levels = [0 15 50 70 85 90 100];
[c,h]=m_contourf(long,lat,sic_mnth(:,:,1),'linestyle','none');
m_coast('patch',[.6 .6 .6]);
m_grid('linewi',2,'tickdir','out');
caxis([0 100]);
colorbar;

If i run it for a single file it is working, the problem is with using the for loop but could not find how to fix it

for m = 7:9;
    if m==7
        datapath = '2007\07\';
    else
    end
    % make list of files in selected folder
    files = dir( fullfile(folderpath,datapath,'ice_conc_nh_2*.hdf') );
    files = {files.name}';
    %
    dd = [];
    %
    % go through all files and add into datamatrix dcube
    for ii=1:numel(files)
        % 
        disp(files{ii}); % show filename on screen to follow progress
        filename = fullfile(folderpath,datapath,files{ii}); % full path to file
        %
        d = h5read(filename,'/Data/data[00]'); % read data
        h = h5read(filename,'/Header'); % read header with d/m/y information
        %
        d = reshape(d,760,1120);
        d(d==-99)=NaN;
        d(d<0)=NaN;
        %
        dd(:,:,ii) = d;
    end
    sic_mnth(:,:) = nanmean(dd,3);
end