The verbs with the general meaning of suggestion and form of the verbs

[ulasozaltay]

in situation 1 ,
I want to say that I told jane, I insisted her to buy a golden neckle ,I would say it in this way ;
''I insisted that jane buys a golden neckle''
in situation 2
If I tell someone else about jane and try to convince that person that jane bought a golden neckle (I have no effect on the fact that jane bought a golden neckle, I am just telling someone else about the fact that jane bought a golden neckle).
I would say it in the same way;
''I insisted that jane buys a golden neckle''
As you see above this sentence (I insisted that jane buys a golden neckle) can have 2 different meanings.
Does it mean the sentence is ambigious by itself and can mean differently depending on context?

[Alan]

The correct form requires the subjunctive, and is unambiguous:

I insisted that jane buy a golden necklace.