Unable to click on button of a pop-up in div using selenium

I'm trying to click on a button inside pop-up. However, webdriver always throws No such element exception. The pop-up is not an alert but a regular element defined inside a . It consists of a message and an OK button. I'm able to verify / locate the message element but unable to click on the button. Following is the html code for it.

<div id="yui_patched_v3_11_0_6_1522928024187_16" class="yui3-widget modal yui3-widget-positioned yui3-widget-stacked yui3-widget-modal yui3-resize" style="width: 95%; left: 334px; top: 167px; z-index: 0;" tabindex="0">
    <div id="yui_patched_v3_11_0_6_1522928024187_18" class="modal-content yui3-widget-stdmod">
        <div class="yui3-widget-hd modal-header">
            <div id="yui_patched_v3_11_0_6_1522928024187_112" class="toolbar-content yui3-widget component toolbar">
                <button type="button" class="btn close">×</button>
            </div>
            <h3>Message</h3></div>
        <div class="yui3-widget-bd modal-body">
            <div class="info-block">
                <table width="100%" cellpadding="0" cellspacing="0">
                    <tbody>
                        <tr>
                            <td width="127">
                                <div id="info_image_errorPriceConditioNotSelect" class="info-image restriction-image"></div>
                            </td>
                            <td>
                                <div id="info_content_errorPriceConditioNotSelect" class="info-content">None selected</div>
                            </td>
                        </tr>
                    </tbody>
                </table>
            </div>
        </div>
        <div class="yui3-widget-ft modal-footer">
            <div id="yui_patched_v3_11_0_6_1522928024187_153" class="toolbar-content yui3-widget component toolbar">
                <button type="button" class="btn yui3-widget btn-content btn-focused" id="yui_patched_v3_11_0_6_1522928024187_500">OK</button>
            </div>
        </div>
    </div>
    <div class="yui3-resize-handles-wrapper">
        <div class="yui3-resize-handle yui3-resize-handle-br">
            <div class="yui3-resize-handle-inner yui3-resize-handle-inner-br">&nbsp;</div>
        </div>
    </div>
</div>

Below is my code through which I'm trying to access the button:-

driver.switchTo().activeElement();
    wait.until(ExpectedConditions.visibilityOf(driver.findElement(By.xpath("//div[starts-with(@id, 'yui_patched_v3_11_')]//div[@id="info_content_errorPriceConditioNotSelect"]"))));
    assertTrue(driver.findElement(By.xpath("//div[starts-with(@id, 'yui_patched_v3_11_')]//div[@id="info_content_errorPriceConditioNotSelect"]")).isDisplayed());
    Thread.sleep(5000);

    driver.findElement(By.xpath("//button[starts-with(@id,"yui_patched_v3_")][text()='OK']")).click(); //Webdriver throws exception here

I'm using selenium 3.9.1 and executing the scripts on chrome.
Any help would be appreciated.

Thanks,
Anuja