Blocks fields internal fields don't respect access modifiers.

I am using a Blocks field but it's own field access modifier are not respected

i.e. Block internal fields access modifier update is set to false, but all fields of the block can still be updated after the document has been created.

update: () => false

Code below:

Main collection

{
  name: 'shares',
  label: 'Transactions',
  type: 'blocks',
  minRows: 1,
  blocks: [
    ShareBlock
  ],
  admin: {
    description: "Buy (pos) and sell (neg) transactions with shares",
    condition: (data, siblingData) => {
      if (data.assetType && data.assetType.includes(AssetType.SHARE)) return true;
      else {
        return false
      };
    }
  }
}

Block component

import { Block } from "payload/types";
export const ShareBlock: Block = {
    slug: 'Share',
    fields: [
        {
            name: 'nrOfParts',
            type: 'number',
            required: true,
            admin: {
                description: "Shares bought (pos) or sold (neg)."
            },
            access: {
                create: () => true,
                update: () => false // <-- not respected
            }
        },
        {
            name: 'pricePerPart',
            type: 'number',
            required: true,
            admin: {
                description: "Share price at transaction"

            },
            access: {
                create: () => true,
                update: () => false // <-- not respected
            }
        },
    ]
};