Because English lacks a gender-neutral singular pronoun, we use "they/them/their" for a single person when the sex is not known. If every single member of the team is male, you can use "him/he" or if every member is female, you can use "her/she" but otherwise, feel confident using "them/they." Or rewrite: If you would like to speak to a team memeber, please call and any one of them would be happy to help.