---
title: "Page won't save or publish"
section: "Errors & Troubleshooting"
canonical_url: "https://support.buildwithhq.com/errors/page-save-problems.html"
reviewed_at: "2026-09-14"
authority: Official
---

# Page won't save or publish

Validation errors, edit locks, and the E021 identity gate.

## In brief

- **Audience:** Builders
- **Related:** Raw JSON mode

## “Someone else is editing”

Pages allow one editor at a time. The banner names who holds the lock. Locks renew while the holder works and expire shortly after they stop — if the named person has left for the day, take-over is offered once their lock lapses.

## Validation errors on save

The editor lists each problem with the block it belongs to. Fix the listed blocks; the save button unblocks when the list is empty. Codes in the `E0xx` range are content-structure problems, explained in the [error reference](error-codes.html).

## The E021 prompt in code view

`E021` means your raw edit removes or duplicates a block identity that future template upgrades depend on. Cancel and restore the identity if you want upgrades to keep working for those blocks; acknowledge only if you understand they'll be treated as new content from now on.

---

Capability review: 2026-09-14. [View the canonical guide](https://support.buildwithhq.com/errors/page-save-problems.html).