Disappointing service ever

Good day... I took my car in for a service on the 23/12/2019 it's first 15 000km service... Om the 18/01/2020 i noticed a oil leak i maybe thought then it was raining alot the roads were wet and maybe the water got under the plate that protects the engine and all those small things... The i noticed but it looks like oil and smells like oil... I took the car in on the 22/01/2020... Monica from lindsay saker assist me, she told me that the rear crank seal is damaged i was sooo mad not at her but at the fact that this car got serviced a month ago and they didn't pick up this problem I'm disgusted Lindsay sakers service went from 10 out of 10 to 2 out of 10, 2 for the ladies booking you in and giving their upmost best... My life is in danger my child life was in danger what if i didn't pick this up??? We have been clients for over 17years to lindsay saker bloemfontein... I don't trust this brand anymore when i get my car back am i going to be save????