H1B Visa denied under 212 (a)(9)(b)(2)

Hi, My H1B Visa was denied by US Embassy during an interview under 212(a)(9)(b)(2) for unlawful presence in US.
I came to US on L1b which expired in Feb 2021. My employer applied for H1B. COS was approved Oct 2020. I got i797A with i94 validity till Oct 2023. So as per my lawyers i did not have any unlawful presence since Feb 2021.
What are my options to get this overturned? Any help or leads is appreciated!