Problem cms page with custom link (rewrite)

[PikNuke]

Hello everybody,

I have a problem for several days that I am trying to solve.
In practice I have created a cms page that incorporates the get parameters:
/content/11-testing
i add parameter get:
/content/11-testing?key=value1.
all work.

But I would like to change the link structure.
I create rules in htaccess:
RewriteRule ^testing/([^/]*)/$ /index.php?id_cms=11&controller=cms&key=$1 [QSA,NC]

This does not work, or rather in part. Why unfortunately it makes me a 301 redirect:
from /testing/value1/ to /content/11-geoseo?testing=value1.
I would like the url to remain as /testing/value1/ without redirects.

I don't know if I have made myself clear. I hope you can help me