I have the same trouble,but now I found where I made a mistake.
At first,I invoke the sign request first then I add the query string
I coded like this:
twitterOAuth.service.signRequest(twitterOAuth.accessToken, request);
request.addQuerystringParameter(“screen_name”, “huanglipeng329”);
then I try to reverse the invoke order.
I coded like this:
request.addQuerystringParameter(“screen_name”, “huanglipeng329”);
twitterOAuth.service.signRequest(twitterOAuth.accessToken, request);
surprisingly,I found the problem solved!