Not acceptable. I don't know laws in the UK but that person should lose their job. Workplace harassment is a serious offense, as you are REQUIRED to be there, so your employer is required to provide you with a safe, harassment-free workplace.
Keep evidence, keep everything, report everything, and keep doing it. Keep personal logs of who you talked to and when, what was said, even if there's no other record. It's possibly going to cost you your "team member" status, but that's what the harasser is counting on. They are sadistic, and they're going out of their way to make your life miserable and endanger your job and peace of mind.
Show them no mercy.