"Doctorul m-a ajutat prescriindu-mi ce i-am cerut."
Translation:The physician helped me prescribing me what I asked him for.
In the present tense the sentence would be:
"The physician helps me by prescribing me what I ask
him for. - Doctorul mă ajută prescriindu-mi ce
îi cer." ("îi" means "him")
In the compound perfect, mandatory contractions appear between pronouns in the accusative or dative case and the verb. Here you can see the accusative "mă" + "a" becomes "m-a" and the dative "îi" + "am" becomes "i-am". Here's two tables of them: https://en.wiktionary.org/wiki/Appendix:Romanian_contractions
I think I saw on mobile phone only "i" hmm... but earlier today I aslo had problems with duo that it showed me full correct answers.... so I just prest enter and got correct. Hm. I raised the problems already. I'm quite sure I saw in the anwer on mobile only "i"... hmm with i-am I would understand. Interesting. And thanks for the answer : )