Android app : User-Agent lost after Redirect

My web application sometimes performs HTTP 301 or 302 redirects. I have blocked access to my application by checking if my user-agent contains the word ‘myapp.’ When there are 301 or 302 redirects, the user-agent header is no longer the one configured in Median. The error seems to come from ‘public boolean shouldOverrideUrlLoading(WebView view, String url) {’ which no longer returns the imposed user-agent but returns the device’s user-agent instead.