An error will occur use the API

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1

The following error is now displayed in HTML format when trying to get a record using the API.
I’ve tried several tables instead of a specific one and I get the same error.
I was able to use it without problems until the day before yesterday.
I didn’t use it yesterday.
I recreated the API Key and tried it, but the results didn’t change.
Is there something wrong now?

---- result ----

    <html>
      <head>
            <meta name="viewport" content="width=device-width, initial-scale=1">
            <meta charset="utf-8">
            <title>Application Error</title>
            <style media="screen">
              html,body,iframe {
                    margin: 0;
                    padding: 0;
              }
              html,body {
                    height: 100%;
                    overflow: hidden;
              }
              iframe {
                    width: 100%;
                    height: 100%;
                    border: 0;
              }
            </style>
      </head>
      <body>
            <iframe src="//www.herokucdn.com/error-pages/application-error.html"></iframe>
      </body>
    </html>
2

I checked it now and it was resolved.
It may have been under maintenance.
Thank you.