Actually, Section 11 provides that, if there exists likelihood of confusion on the part of the public, which includes the likelihood of any kind of association with the earlier trade mark and the later trademark also provides same kind of goods/services as that of earlier trademark, only then the later trademark shall not be registered.
So, have you been denied registration of your selected trademark?
The degree of likelihood of association should be as, that the later trademark gives general public an impression of similarity with former trademark on first sight or cursory glance. Same kind of goods/services means, type of business of both firms is as similar that it gives impression to general public that the later trademark is also associated with the firm having former trademark.
Therefore, see if your trademark gives any kind impression of association with that earlier trademark. See if your firm also provides same kind of goods/services as that of the firm/company who has registered that former trademark earlier than you. As you have been provided the details of the former similar trademark, you can easily check that.
You can make such minor alterations in your trademark to the extent that the 'similarity' is removed.