I know nothing about growing Plumeria, but those who do will need more information before they can help you. Can you provide a picture and a location? Is this plant growing outside in a warm climate or indoors in a cold one? What care regime does it have? Soil? Water?

pix of plant and the pot its in

what media did you use..

how do you water.. did you moisten media before repotting...

indoors or out. if outside.. big city name..

do you use supplemental light indoor.s. where is it located indoors..how much light does it get ...

have you overwintered it indoors in prior years???

welcome to the forums.. give us lots of facts to work with.. and we can probably help ...

loss of leaves after transplant indicates sever stress related tot he process... we have to now figure out how to de-stress it....

ken

I grow my plumeria outdoors in Anaheim CA. I used a Palm-Cactus-Citrus soil mixture. The soil was semi dry when I transplanted the plumeria into the bigger pot. I use a moisture meter to help me figure our when my plants need watering. I was adding water to the transplanted plumeria about once a week, but once the leaves fell off and the stems became soft, I read online to allow the soil to dry out. Attached are photos taken today.

does the pot have drain holes???

is the pot in full sun ... did you out it in full sun after transplant into dryish media???

move it the bright shade.. and let it near dry between waterings.. i prefer you learned how to use you finger rather than a gizmo to gauge moisture in the media ...

it we can remove the stress.. and settle the plant down.. most can releaf ... but that will take a while.. and you have to stop trying to love it to death in the meantime....

just water properly.. and no direct sun for now...

its severely stressed..not hungry.. fert is not a response at this time ....

ken

The pot has several holes for drainage and is kept in bright shade.