The sections of the California Probate Code that applies to the duties and liabilities of the conservator are 2400 - 2410. It sounds like you may be interested in 2401.3. Please see an attorney to proceed with any legal action. This is a complex area of law and you should have someone helping you.
This is a general information answer ONLY and does NOT create an attorney-client relationship. Without detailed facts about your case, I cannot provide specific legal advice and this answer is not intended to be taken as legal advice.
Can't answer if they were liable because you didn't present any facts to show negligence or breach of duty. Just because there was a loss doesn't mean they are liable. Check Probate Code Section 1800, 2350-2595, et seq. Start with these. If there is negligence, then get an attorney to help.
California Probate Code Sections 2400-2410 deal with conservator duties and liabilities.
However, I would need more information to provide an answer to your second question.
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