My brother got mum to change their will so now it's just him is the executive. Can he do this?

Yes it is .
And we don't even know which bank it's at
We are trying to find it

Lanie, take your LPA for finance to the bank that operates your mother's joint saving account and get advice from them.

Is your LPA now registered through the OPG?

He did but mum cancelled it ...my sister and I have poa now for both finances and health& welfare. Mum as very short term memory loss in fact she is much worse now .
Bro got poa in 2015 and I think he did everything then .he still as mum's savings and won't give them to her .
We are applying to the cop but not sure anything can be done because there in a joint account with him ?? We are in the uk....

As Jeanne said, executor is for after death and does not do anything to change the POA. Does your mom have you and sis as financial and medical POA?

The position of executor applies to handling the will, probate, paying creditors, etc. It all happens after the person dies. From what I've heard it is a heck of a lot of work.

Being executor gives no one the authority to change bank accounts or handle the finances while the person is living. Does your brother have POA also? What is the status of your mother's mental health at this time?

My brother took her to a solicitor and changed it making him the only exceutor
Maybe 2015/16 Not sure but he did it why I do t know
My sis and I do not have a relationship haven't for for 30y since he married his wife didn't want to get on with us ..

Is this in the UK?

When did your mother change her will, and how did she go about it? Did she do it with the help of a solicitor, or what?

We have papers yes reg poa for both

Yes
And no my mum Lives with me since last November and my brother as not been to see her

Lanie, remind me, is your brother your mother's primary caregiver?

When you say your sister and you have power of attorney, is this a formal document that is currently in force?

He as the will why would her do this .mum as Alzheimer's he also closed all accounts and put all her savings in one joint account with him
What can we do my sister and i have poa now can we do anything .please advise