Brief Answer:
Cortisol

Detailed Answer:
I have seen the attached lab result.

A 24 hour urinary free cortisol test is performed to look for a condition called endogenous Cushings syndrome.
Cushings syndrome refers to the excess of glucocorticoids in the body. Glucocorticoids are one of the several types of hormones made by the adrenal glands. The word 'steroids' is often used casually to refer to glucocorticoids.

The word 'endogenous' implies that the body is making excess steroids in an unregulated manner, as opposed to 'exogenous' where the individual is taking 'steroids' from outside, typically in the form of medications, and that results in 'steroid' excess in the body.

Now, there are several ways to test for 'Endogenous Cushings syndrome'. The first round of tests are called screening tests, and are followed later by more complex type of tests to confirm the diagnosis and search for the exact cause.

You have undergone one type of screening test which is the 24 hour urine free cortisol. And yes it is positive. But latest guidelines by endocrinologists recommend that at least 2 out 3 screening tests come positive before one proceeds to the next step.
I know you have done the same urine test 3 times but it is preferable to have 2 to 3 different type of screening tests done.
So the other two are:

A) Overnight dexamethasone suppression tests:
The doctor prescribes 1 mg of a medication called dexamethasone that is to be taken at midnight, and the next morning sharp at 8 am, a blood sample for serum cortisol is taken.
This is presuming you have a conventional sleep wake cycle ie you do not work night shifts. If you do the timing of the test needs to be changed to match the reverse routine

B) Midnight salivary cortisol
This is a saliva test done at midnight. The lab will give you a kit with instructions on how to use the swab and return it the next day to the lab.

If one or both of these testa also come back abnormal you should consider further evaluation, preferably by an endocrinologist because each of these tests have caveats and require experience in interpreting.
In fact these tests should be performed only if the index of suspicion for "Endogenous Cushings syndrome' is high.

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Brief Answer:
Follow up

Detailed Answer:
The diagnosis and management of endogenous Cushings syndrome are exquisitely complex and directed at the cause.
The most common cause is a pituitary tumor and the conventional treatment starts with surgery. But again, all treatment decisions are individualized based upon several factors.
The key first step in your situation is to first ascertain the diagnosis.
Endocrinologists are the most qualified doctors to handle this tricky condition.
This entails a thorough in-person examination in addition to systematic lab testing.
Salivary cortisol at midnight is a useful test

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