NHTSA Complaint #11469686 — 2015 HYUNDAI ELANTRA

i only have 4,100 miles on my vehicle. several months ago i was driving and i could not go over 40 mph, even putting the pedal to the floor. NO WARNING LIGHTS EVER CAME ON, could not find the transmission plug to check that fluid. brought to the dealer even though vehicle was running okay several days later to find out why this happened. their machine did not pick up anything wrong. i only do city driving so i rarely go over 40 mph. dealer blamed bad gas. could it be possible that because i hardly ever go over 40 the vehicle put itself in limp mode. dealer did not check my transmission fluid even though i asked them to. the us postal service sends me pics of the mail i will receive for that day. around june 14 2022 it showed a letter from 2015 hyundai elantra official business penalty for private use 300 important vehicle information address change? please contact our customer service dept- can you please send me that letter