Why does the 301 redirect add the url?

Question

htaccess

I write the following in htacces.

Redirect 301 /about_programms/average/ http://www.sitename.ru/foreign/

But when you go to /about_programms/average, for some reason it redirects to /foreign/average/
And so with all multilevel links, i.e.
Redirect 301 /a/b/v http://www.sitename.ru/a/
Will turn into www.sitename.ru/a/b/v
Site on Bitrix. What could be the problem?