Kamala accused of lying about Trump and border security

Kamala Harris is accused of lying to everyone in the audience and whomever watched this video. She tried saying that Donald Trump doesn't care about border security. However, that's an obvious lie because Donald Trump has been very outspoken about border security over the years. Donald Trump was trying to build a wall along the southern border in hopes of making it more secure and preventing people from crossing into the country illegally.

Kamala's claim is rated as a huge lie. She's been vice president for the last 3+ years, so if she cared about the border at all, then she could have done something about it herself. Did she?