Http request using multipart/form-data using pl/sql is ignoring UTF-8 and sending invalid characters

Hi,

I am trying to send an HTTP POST request using pl/SQL. The content type at the header level is 'multipart/form-data'. It looks like the request is not being sent with UTF-8 encoding, which causes issues when there are Cyrillic characters in the body. Below is the code snippet. If I send the same data with the header 'text/plain;charset=utf-8', it works just fine but fails with the 'multipart' header. The database character set is AL32UTF8.

Any help is greatly appreciated.

DECLARE
req UTL_HTTP.req;
res UTL_HTTP.resp;
body CLOB;
url VARCHAR2(4000) := 'http://webhook.site/c75bf6bf-fbcb-451c-8de6-d336bfe29655';