2xx - "Yup, that worked, probably"
200 is usually a good thing.
400 Bad Request - “I haven’t got a clue what you are asking”.
The way you formed the API URL is likely to be wrong, double check !
401 Unauthorized - "I don’t know who you are, you need to authenticate yourself"
You will need to do some form of authentication … check the API documentation
403 Forbidden - “I know who you are, but I am not letting you at that”/
In this case you have probably authenticated OK, but you don’t have permission to do what you asked. Might be worth looking at SCOPEs you have asked for ? Also check on the method (PUT, GET etc) here as well.
404 Not Found - “I can’t find the thing you are looking for” (or I can but I am not going to tell you that)
We all know this one … but in an API context you need to check the “resource” which tends to be the numbers after the words
So, in this case, the fruit with the resource id 1234567 doesn’t exist
405 Method Not Allowed - "I know what you want to do and on what, but you can’t do it that way"
Check the method in your setup, are you doing a GET when it wants a POST ?
5xx - “It’s all gone horribly wrong at our end”.
Chances are it is them not you.