You should consider that
CookieManager.getInstance().setAcceptCookie(true);
doesn’t work from lollipop(API21) and above. You should check and use appropriate function for that case:
if (android.os.Build.VERSION.SDK_INT >= 21) {
CookieManager.getInstance().setAcceptThirdPartyCookies(mWebView, true);
} else {
CookieManager.getInstance().setAcceptCookie(true);
}