co working office

After 9 months of working from home with my husband and cat, I decided to look for a co working space so that I could ‘go’ to work again. Even though I see all my clients on zoom right now.
I found an amazing place that is very Covid safe.

I got the first month free. It was part of a promotion they were doing. I decided to stay and the rent is $500 a month ‘all in’ Then when they sent me the contract they added tax. Which I should have realized but didn’t and they didn’t mention it. Nor did they mention the security deposit.
After some careful thought I signed a year long contract.
Today I got an invoice for January plus the security deposit and a note to say it needs to be paid by Dec 15th.
I was under the impression I would be charged this on Jan 1st since that’s what usually happens with rent and no one had told me any different.

I love the office space, and the people here are friendly
However I am feeling very ‘off’ regarding the money.

C. Rent and security deposit for Jan rent being charged in December
T I am being taken advantage of
F Lonely
A Emailed them asking them if there’s an error.
R I’ll be taken advantage off (I wrote this because I think the thought line and result line is the same)

Any advice?