Calling API from SQL Server [Issue] - sql-server

Question

I am working with API and MSSQL. I need to call an API from SQL Server. But On execution, its response is null. Can anyone list errors if some in the queries?
The API responds but the issue is it shows error in Authentication while I'm using exact correct credentials. It's a POST API.
This is the only way I found correct on browsing the whole a day on Google. Can someone help or list errors?
DECLARE #authHeader NVARCHAR(MAX)= 'Basic XXXXXXXXXXXXXXXXXXXXXXXXXXX-XXXXXXXXXXXXXXXX'
DECLARE #contentType NVARCHAR(64) = 'application/json; charset=utf-8'
DECLARE #appVersion NVARCHAR(20) = '3.2.1'
DECLARE #appkey NVARCHAR(50) = 'XXXXXXXXXXXXXXXXXXXXXXXXXXX'
DECLARE #deviceId NVARCHAR(50) = 'XXXXXXXXXXXXXXXXXXXXXXXXXXX'
DECLARE #deviceType int = 1;
DECLARE #language int = 1;
DECLARE #status NVARCHAR(32);
DECLARE #statusText NVARCHAR(32);
DECLARE #Body as VARCHAR(8000) =
'{
"itemId":"XXXXXXXXXXXXXXXXXXXXXXX",
"itemType":XXXXXXXXXXXXX,
"liked":"true"
}'
DECLARE #responseText NVARCHAR(2000);
DECLARE #token INT;
DECLARE #url NVARCHAR(256) = 'https://api-stage.testapp.com/v4/test';
Exec sp_OACreate 'MSXML2.ServerXMLHTTP', #token OUT;
EXEC sp_OAMethod #token, 'open', NULL, 'POST', #url, 'false'
EXEC sp_OAMethod #token, 'setRequestHeader', NULL, 'Authentication', #authHeader
EXEC sp_OAMethod #token, 'setRequestHeader', NULL, 'Content-type', #contentType
EXEC sp_OAMethod #token, 'setRequestHeader', NULL, 'appVersion', #appVersion
EXEC sp_OAMethod #token, 'setRequestHeader', NULL, 'appkey', #appkey
EXEC sp_OAMethod #token, 'setRequestHeader', NULL, 'deviceId', #deviceId
EXEC sp_OAMethod #token, 'setRequestHeader', NULL, 'devicetype', #deviceType
EXEC sp_OAMethod #token, 'setRequestHeader', NULL, 'language', #language
EXEC sp_OAMethod #token, 'send', null
Exec sp_OAMethod #token, 'setRequestBody', null, 'Body', #body
EXEC sp_OAGetProperty #token, 'status', #status OUT;
EXEC sp_OAGetProperty #token, 'statusText', #statusText OUT;
EXEC sp_OAGetProperty #token, 'responseText', #responseText OUT;
PRINT 'Status: ' + #status + ' (' + #statusText + ')';
PRINT 'Response text: ' + #responseText;
Select #ResponseText as Response