In order for a protonated acid to lose a proton, the pH of the system must rise above the pKa of the acid.
ɪn ˈɔːɹdɚ fɚɹə pɹˈoʊtənˌeɪɾᵻd ˈæsɪd tə lˈuːz ɐ pɹˈoʊtɑːn, ðə pˈiː ˈeɪtʃ ʌvðə sˈɪstəm mˈʌst ɹˈaɪz əbˌʌv ðə pˈiː kˈɑː ʌvðɪ ˈæsɪd.