Cannot grant access and connect to app


I am having trouble connecting my website to the app, 9/11 passed only the API Details Validation/ Authorisation vailed ( Username and Application Password are not authorised. )

the error:
{“code”:“rest_no_route”,“message”:“No route was found matching the URL and request method.”,“data”:{“status”:404}}

i tried:
-double check application username and password
-previous php and wordpress version
-set permalinks to post name
-re install wordpress completely

i am working on a clean install of wordpress

Hope anyone can help me,
Greetings Roelien