For what has been a reliable online qr code generator for years has finally been shut down, having been deprecated in 2012! If you try to use it you will get a 502 error.
Here is a short listing of some alternatives:
https://api.qrserver.com/v1/create-qr-code/?size=70x70&data=ExampleText
https://quickchart.io/qr?ecLevel=L&text=ExampleText
https://qrcode.tec-it.com/API/QRCode?data=ExampleText
Visit their api pages for instructions on more detailed use...