93 miata with transmission leak, help!

I got a 93 miata from some old lady for $1,500. It was sitting for 10 years n was more likely flooded bc the rust n gunk in the gas tank n rust in cylinder 4 spark plug tube. As of today i got it running n driving fully, new fuel pump, filter, etc. well… first drive was bad bc low transmission fluid, i assumed it was gonna be low bc it was flooded n sat for 10 years bc so was the engine oil. I filled the transmission fluid n engine oil n after enjoying it without issue, parked for 10min then called it a day. Went to put it in my garage n looked back to see a decent size puddle of transmission fluid. I have no clue what it could be if anyone has any ideas or knowledge with these bc this is my first miata.