Family Dollar complaint: Manager the price

So I went in last night to get some accessories for my house. Saw that they had double sided duck tape for 2 dollars and there were 6 left so I continue to put all in my basket and proceeded to the check out lane. When I got to the check out lane this manager by the name of Christen and the store number is 10107. Anyways she I’ll get her name to be sure but when she rung me up the price said 3 dollars a piece but the sign said 2 dollars. So there was a dispute and I was very polite in telling her that this was false advertising, and I walked out and she told my grandchildren that we were not allowed in the store no more… Which my grandchildren are 11 and 9. As I was in my vehicle Christen came out of the store and took pictures of my vehicle and stated that her team was going to back her up and that I threaten her which I never did. I called law enforcement and they said that they didn’t see this dispute as an emergency and never came.! The farthest rude thing I said after I had asked her politely to please be quiet was to shut the hell up after her insults towards me. If you roll the cameras back you can see that I was very polite and held my composure even tho she was very rude and lied about me threatening her. I have been a loyal customer with family dollar for 5 plus years and never have I ever been this disrespected before by any employees at family dollar.