How long does it take for a IUD to be ordered

3 1/2 weeks ago I went in for IUD consultation then a week later I called them for the status on getting the IUD and they told me my IUD was approved but will take some to until it comes in. I called again today and it still isn’t in yet, the only answer they gave me is sometimes it comes in fast sometimes it doesn’t… does it normally take this long or should I find a new doctor?