My question involves a security deposit in the State of: CA
I recently moved out of an apartment I shared with one other person. Both our names were on the lease and we were the only tenants for the duration of our stay. We also both vacated the apartment at the same time, but she left no forwarding information or valid phone number for anyone to contact her. We did not share the same circle of friends, and she changed jobs during our residence there so all the information I had for her is obsolete. I cannot even find her online because she uses at least 7 or 8 aliases that I know of.
The issue at hand is that I was mailed a check (postmarked 25 days after we left the apartment) with both of our names on it and I am unable to retrieve my portion of the deposit. I visited the management offices and requested either a check for half the remaining deposit amount with just my name on it, or a check for the full amount with just my name on it (hey it was worth a try). I was told that without a signed release from the prior roommate stating that she waives her right to the deposit amount they are unable to help me in any way. They said that by California law they must return the full amount in one check, with all tenants names on it and could not provide me with a separate check for a lesser amount.
Is this correct? What, if any, action may I take to get my deposit amount back? Is there a certain amount of time before the deposit is automatically considered forfeit by the other party, thereby allowing me to claim the full amount? Lastly, since I did not receive notice of the deposit from the apartment manager within 21 days is a claim for double the deposit amount viable? When replying, if you could cite the laws or trials pertaining to the topic that would be very much appreciated.
Thank you for your assistance

