gatsby – I am having issues in Graphql query cannot query field slug on type Frontmatter

ERROR #85923 GRAPHQL.VALIDATION

There was an error in your GraphQL query:

Cannot query field “slug” on type “Frontmatter”.

If you don’t expect “slug” to exist on the type “Frontmatter” it is most likely a typo. However, if you expect “slug” to exist there are a couple of solutions
to common problems:

• If you added a new data source and/or changed something inside gatsby-node/gatsby-config, please try a restart of your development server.
• You want to optionally use your field “slug” and right now it is not used anywhere.

It is recommended to explicitly type your GraphQL schema if you want to use optional fields.

File: node_modules/gatsby-redirect-from/gatsby-node.js:44:15

See our docs page for more info on this error: gatsby.dev/creating-type-definitions

This is the error I am facing while executing gatsby build.