I'm sorry to read that your garnishment order has not been terminated yet, although you've indicated that settlement was reached and the debt was satisfied. As you probably know, your employer cannot simply stop withholding your garnished wages until they get a valid order to do so. You may want to call the collector again and ask for written proof that they indeed have submitted the necessary 'paperwork' to stop the garnishment, but depending on your county's laws, the collector's attorney may have to also file a motion and order to terminate the garnishment with the county superior court. A satisfaction and release will then be provided to your employer. Garnishments can take take time to legally enforce and take time to terminate, but a few pay periods is getting a bit long, in my opinion.
For your troubles, ask that the creditor also have their counsel motion the court to vacate the judgment against you, rather than merely filing a satisfaction of judgment - it will look better on your credit report down the road. Also ask that they waive filing any forgiveness of debt with the IRS if you settled for less than the full judgment amount - otherwise, you may get a 1099 at the end of this year where any amount forgiven may be considered taxable income.
If you do not get a satisfactory response within a day or so of calling the creditor again, inform the creditor that unless the garnishment order is terminated prior to the next pay period, you're going to retain an attorney to force a turnover of funds due, as well as the costs and fees incurred to get back what is rightfully due to you. Best of luck; I hope you get this matter resolved quickly and to your satisfaction.