You are correct - because you have gotten a tax benefit on the insurance premiums as Self-employed health insurance premiums, you should not try to enter them again in Georgia.
The Georgia High Deductible Health Plan deduction includes only the HDHP premiums that are not already accounted for on the federal return.
Therefore, you are unlikely to need to enter anything in this field on the Georgia return.
The Georgia instructions say
"20. An amount equal to 100 percent of the premium paid by the taxpayer during the taxable year for high deductible health plans as defined by Section 223 of the Internal Revenue Code. The amount may only be deducted to the extent the deduction has not been included in federal adjusted income and the expenses have not been provided from a health reimbursement arrangement and have not been included in itemized deductions. " See the Georgia instructions (page 15). Note that when you took the Self-employed health insurance deduction, your HDHP premiums were removed from federal adjusted income.
