Follow these steps to fix that.
If you have a wordpress hosting account, log in to cPanel.
Go to File Manager.
Navigate to the public_folder and look for the file php.ini if you can´t see one use the new file button to create a new php.ini.
Right click the php.ini and go to edit.
Add these lines of code:
upload_max_filesize = 40M
post_max_size = 40M
Save the changes and see if you can now upload the images. If not follow the steps below.
Go back th cPanel and File Manager.
Make sure you select the show hidden options button when you enter the file manger.
Add this code into your .htaccess:
deny from all
Change username to your username and remove the quotes.
You should now be able to upload items up to 40mb.