This is a very common issue with revocable trusts and it results from not respecting the formalities of the trust.
In order for a revocable trust to work as intended, that is, to avoid probate, your assets must be transferred to the trust. For instance, if you own a house, the deed needs to be changed to reflect that you own the house as trustee of your revocable trust. The same applies to bank accounts and other financial assets. It is important to note that assets having beneficiary designations or joint owners do not need to be placed into the trust to avoid probate since they avoid probate by their very nature.
Many people often create revocable trusts and do nothing after leaving their attorney’s office. Sometimes it is the fault of the client, other times it is the lack of good advice from the attorney. In either case, when assets are not transferred to the trust and that person dies, a probate proceeding is required to manage those assets. This defeats the purpose of the revocable trust.