I get paid hourly and I get a % of commission. My employer reports my hourly with W2, but reports my commissions with 1099-MISC. Is that correct, or should it all be W2?

I am a real estate assistant. My hourly wage gets reported as W2 income. I also get a percentage of my brokers commission when he/she sells a house. They report that as 1099-MISC. Should they be doing that? I feel like it should all go on W2 as I am not self-employed.