oracle database 12.1.0.2 HTTP request

I want to make a HTTP request it will be between my Oracle Database 12c Enterprise Edition Release [login to view URL] - 64bit Production and sites provide us service using I want to make http request using Pl sql on oracle 12c Database but there is error fatal ssl error I think I have to add website that I want to make a request on oracle wallet manager but Its not work so I want to fix this issue and when I tried to enter certificate on wallet manager it show me this error [Error] Execution (1: 1): ORA-29273: HTTP request failed ORA-28759: failure to open file ORA-06512: at "SYS.UTL_HTTP", line 368 ORA-06512: at "SYS.UTL_HTTP", line 1118 ORA-06512: at line 27