The best way would be : 'If you still have questions,please send your concerns to my email box' Concern and concerned are used in several different contexts : 1) Please send in your concerns to < email address>. - in this context 'concerns' mean doubts,questions or queries regarding something 2) Please send in your points concerning {topic of discussion} to < email address>. - in this context 'concerning' means 'about' or 'regarding' . Eg. Issues concerning hygiene are taken care of by the ministry of health 3) Please send in your queries to the department concerned /concerned department. - here concerned means 'respective' . Eg. If you encounter any problems during the installation of your software, please contact the concerned department [ tech support]. 4) Concern as a noun can also mean a firm/business establishment, interest or a feeling synonymous with worry

Hi Arena. First, " If you still have question" should be " If you still have questions" or " If you still have a question" The phrase "please send your concerning point to my email box." is better said "please send your concerns to my email box." Concern can be used as a noun. The is no need to put the word "point" in the sentence.

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