Search for button in iframe

I have an application with multiple iframes in the same screen. These iframes have different names every session, so I would like to search within the application for a button within one of the iframes with the name "Pesonal". This iframe-name should be saved to be used in another method. Anybody an idea how to do this?

Please close / delete this topic as I have found the solution:

public WebElement findElement(By locator) {
    driver.switchTo().defaultContent();
    //list all iframes
    List<WebElement> iframeList = driver.findElements(By.tagName(("iframe")));
    final List<WebElement> foundElements = new ArrayList<>();
    iframeList.forEach(iframe -> {

        driver.switchTo().frame(iframe);
        List<WebElement> foundElementList = driver.findElements(locator);
        if (foundElementList.size() > 0) {
            foundElements.addAll(foundElementList);
        } else driver.switchTo().defaultContent();
    });
    return foundElements.get(0);
}