What happens if you miss you i-90 Biometrics appointment?

I was on my way to my biometrics appointment when my boyfriend got a flat tire in the freeway and i completely missed my appointment. I called the 800 number and the woman said the only way to contact them was to sent back the paper i had to to take to biometrics appointment and mark the box requesting a new appointment. I did that and its been almost a week. what can I do? what will happen if they deny me? will I loose my money and not be able to renew my green card? im so confused.