Experienced Support Rep
When applying for any position, it helps to showcase your experience performing in that role. Below is an example summary you can refer to from my colleague's application for the HubSpot Support team.
"Experienced customer service rep seeking a support position with an expanding tech company. Possesses a bachelor's degree in marketing communications and has over 3 years of experience in customer service roles. Highly skilled communicator who meets deadlines and ensures customer satisfaction."