How can i cancel a line and not lose my free lines.

In an attempt to save some money, we went to review our family plan.

We are on an old Magenta family plan. Taxes and fees included.

8 lines in total

L1 / L2 = $140

L3 = $30

L4 = $30

L5 = $30

L6 = $30

L7 = 0 = Service Promo with New Line (ID230233)

L8 = 0 = Service Promo with New Line(ID250259)

Total = $260 - $30 autopay discount ($5x6 paid lines) = $230

Line 6 is no longer needed. He not been needed for the past 4 months. I've been considering cancelling but I've heard horror stories. Like them just cancelling one of my free lines instead. So i would be paying the same but one less line. My goal would be to bring down the bill to $205 with 7 lines.

In the past i've walked into the stores and just called 611. Are these still the best way to go about getting this done? Any key words or phrases i need to say to them?

Back in the day, we just called and just go straight to retentions to try to get a $5-20 one time discount those were the good old voicestream days.