I rented office space five years without a lease.gave landlord 30 day notice.How long does he have to return?

I had a commercial lease for the first five years of renting office space but the landlord neglected to renew the lease. Ive been renting for an additional five years without a lease.(ten years total) I gave a thirty day notice to move to another office space in the same building with the same landlord. I requested a return of my initial security deposit. How long should i wait for that returned security deposit? He is requesting a new security deposit for the new office space. Is that legal?
The space I am moving to is half the size of my last rental. The rent is 250.00 instead of $550. The new deposit is $250 on the smaller unit. The old deposit on the larger unit was $500. I have not received the old deposit back. I do not need the larger space because business is slow. The landlord agreed to the move. Thats no problem but has not returned my initial deposit.

Why would you get your initial security back? That makes no sense. Especially if you are still in the building with the same landlord.
If you are moving to a bigger space, the security on that unit is going to be more, and that is why he is probably asking for a new deposit. Even IF you are downsizing, in 10 years rent has gone up and your initial deposit probably would not cover what he charges at the unit you want to rent now.
You will not get your security deposit(s) back until you completely vacate the building.