Answer: I hope you tried ground layering to root it into a small container rather than air layering. Ground layering works well with vines, but you need to be patient using this technique.
It is illustrated here as Fig. 9.
Keep in mind that the roots will have to support the plant once it is separated, and take up enough moisture to keep the foliage hydratged, so you need a fairly substantial amount before separating the plant off. If you used a small pot, with a few inches of growig tip, ideally the pot would be filled with roots, for example. Once separated, make sure the plant is adequately watered and provide a high humidity location for it. You might enclose the plant in a loosely closed plastic bag and keep it in a bright location but out of direct sun for a few weeks to assure the humidity is high.
I think layering is more commonly used on outdoor vines as it is a slow process, taking up to a year. Another method to try with an indoor plant that might be easier is rooting tip cuttings, (see Fig. 8) although again you have to be patient and keep the humidity up. Here is some general information on propagation you may find helpful in reviewing your techniques. You may need to cut and paste the complete url to make it work correctly.
Good luck with your jasmine project!
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