Every sensor plus its applicator comes in its own sealed yellow box like this. (Package may look a bit different in different countries but contents will look the same, I opened one of mine to show you.)
In the box are the two parts you need as in the picture, plus a leaflet with instructions.
Can it be your doctor just gave you the empty box plus waste after applying the sensor in case you needed to contact the manufacturer?
Your profile says you're on metformin only, is that correct?
Being in the US, does your insurance pay for the sensors or do you have to self fund?
I've never heard of someone getting Libre funded on metformin only, but things may be different in the US depending on insurance.
If you have to pay for the sensors you can just buy them over the counter in the US, as far as I know, no need for a prescription.
If your insurance covers it if prescribed, I'd get back with your doctor and ask what went wrong.
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