Why can't i get legal representation for my case?

I went into a 7-11 store 3/22/21 at 2:30 am, ask the cashier (male) for gas , he began ringing me up but skipped over the reward part of the transaction,( 7-11 has a reward program that they ask customers to participate in , with every purchase you enter your phone number and get points toward discounted or free stuff.) I ask the cashier if he would go back to the reward portion of the transaction so i could enter my number for the points, which he replied NO! Theirs no F*****G rewards for gas! I asked him if he would go back anyway so i could enter my number, and again he replied NO! I told you theirs no points for purchasing gas and added get the F**K out of here i refused he told me he would F**K ME UP! while coming from behind the counter at me with a long handled butchers knife , waving it and approaching me while still threatening my life! I then exited the store because i did'nt have my phone on me to call the police. police viewed the video and arrested him Aggravated Assault!