(ca) Poa Isolating Parent - Estate Law Advice

There are separate estranged siblings from myself who have been granted POA status for our parent. This parent has had some health issues around mobility. I live in (IA) now and my access to said parent is being revoked.

Both the medical and financial POA have had interactions with the lawyer preparing the will etc, without other family members present. That alone led some family to request the documentation, but no information has been provided by either POA. The parent granted this request verbally to the lawyer, however it is now being deemed too stressful to discuss and now all outside contact with the parent is being limited. No child may call them.

To date the POA has not answered questions as to whether the parent is capable of making their own choices. Medical information is being withheld from the rest of the family, and payment for reimbursement for costs associated (food etc.) with the parent are not being paid or delayed at the POA discretion.

Is this an overreach? What can be done?