You can add this to your code to dynamically pick the default profile name value from the instance.
declare @profile_name varchar(56)
select @profile_name = a.name
from msdb..sysmail_profile as a
inner join msdb..sysmail_profileaccount as b
on a.profile_id=b.profile_id
inner join msdb..sysmail_account as c
on b.account_id= c.account_id
EXEC msdb.dbo.sp_send_dbmail
@from_address='',
@recipients= @oper_email,
@subject = @strsubject,
@body = @tableHTML,
@body_format = 'HTML',
@profile_name=@profile_name