notification after creating post does not work

I did the routine in the onesignal homepage

but I could not send notification for creating post in gutenberg

so I did the solution onesignal homepage gave

https://documentation.onesignal.com/docs/troubleshooting-wordpress-web-push#debugging-with-gutenberg

but I can’t solve the problem

The Chrome Dev Tools console said as below

{recipients: Array(0), status_code: '400', response_body: '{"errors":["Please include a case-sensitive header…al.com/docs/accounts-and-keys#section-keys-ids"]}'}
recipients
: 
[]
response_body
: 
"{\"errors\":[\"Please include a case-sensitive header of Authorization: Basic <YOUR-REST-API-KEY-HERE> or Bearer token=\"<YOUR-REST-API-KEY-HERE>\" with a valid REST API key.\"],\"reference\":[\"https://documentation.onesignal.com/docs/accounts-and-keys#section-keys-ids\"]}"
status_code
: 
"400"
Prototype
: 
Object

What can i do??

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