🐛 502 error when editing collection

**Describe the bug**
502 Error when trying to edit a collection.
This is only effecting some users


**Applicable Versions:**

- Decap CMS version: "netlify-cms-app": "^2.15.72"
- Git provider: GitHub
- OS: Windows
- Browser version: Chrome

**CMS configuration**

https://github.com/SSWConsulting/SSW.Rules/blob/main/src/cms/config.js

```js
import { generateGuid } from '../helpers/generateGuid';

var configJson = {
config: {
backend: {
name: 'github',
repo: 'SSWConsulting/SSW.Rules.Content',
branch: process.env.CONTENT_BRANCH,
open_authoring: true,
auth_endpoint: '/api/auth',
always_fork: true,
base_url: process.env.API_BASE_URL,
use_graphql: true,
},
site_url: 'https://www.ssw.com.au/rules',
publish_mode: 'editorial_workflow',
logo_url:
'https://www.ssw.com.au/ssw/logo/SSWRules/Downloads/SSW%20Rules.png',
show_preview_links: false,
search: false,
media_folder: 'static/assets',
public_folder: '/assets',
collections: [
{
name: 'rule',
label: 'Rule',
sortable_fields: [],
folder: 'rules',
media_folder: '',
public_folder: '',
slug: 'rule',
path: '{{uri}}/rule',
create: true,
fields: [
{
name: 'type',
label: 'Type(e.g.rule / category)',
widget: 'hidden',
default: 'rule',
},
{ name: 'title', label: 'Title' },
{
name: 'uri',
label: 'uri (a unique identifier for the url)',
pattern: [
'^[a-z0-9_-]*$',
'Must only contain lowercase alphanumeric or the "-" and "_" characters',
],
},
{
name: 'body',
label: 'Body',
widget: 'markdown',
default: `Instructions for creating rules can be found at [How to Create Rules](https://github.com/SSWConsulting/SSW.Rules.Content/wiki/How-to-Create-Rules). Follow the steps below and replace the text in this box with your own content.

1. Place your intro here. This will show in the blurb.

2. Place your content here. Markdown is your friend. See this [example rule](https://www.ssw.com.au/rules/rule) for all the things you can do with Rules.
3. Submit your rule for review.
4. Add your rule to a category. See [How to Add and Edit Categories and Top Categories](https://github.com/SSWConsulting/SSW.Rules.Content/wiki/How-to-Add-and-Edit-Categories-and-Top-Categories).`,
},
{
name: 'authors',
label: 'Acknowledgements',
widget: 'list',
fields: [
{ name: 'title', label: 'Name' },
{ name: 'url', label: 'Profile url', required: false },
{ name: 'img', label: 'Profile image', required: false },
],
default: [{ title: '' }],
},
{
name: 'related',
label: 'Related',
required: false,
widget: 'list',
field: {
name: 'relatedRule',
label: 'Rule uri',
hint: 'The URI for the related rule, i.e. label-your-assets',
pattern: [
'^[a-z0-9_-]*$',
'Must only contain lowercase alphanumeric or the "-" and "_" characters',
],
},
},
{
name: 'redirects',
label: 'Redirects',
required: false,
widget: 'list',
field: {
name: 'redirectUri',
label: 'Redirect uri',
hint: 'The URI for the old rule, i.e. label-your-assets',
},
},
{
name: 'created',
label: 'Date created',
widget: 'datetime',
field: {
name: 'relatedRule',
label: 'Rule',
widget: 'relation',
collection: 'rules',
search_fields: ['title'],
value_field: 'uri',
display_fields: ['title'],
options_length: 5,
},
},
{
name: 'archivedreason',
label:
'Archive this rule by adding a reason (leave blank to unarchive)',
required: false,
},
{
name: 'guid',
label: 'GUID',
widget: 'hidden',
pattern: [
'^[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-5][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}$',
'Must be a valid GUID',
],
default: generateGuid(),
},
],
},
],
},
};

export default configJson;
```