Please help me understand whether the correlation coefficient is weakened by the sample size in the study by Sim et al., (2015).

According to Cohen (1992, Table 2, p. 158), for the stated correlation coefficient, sample size and alpha value in Sim et al. (2015), powerful conclusions about a correlation test would require a sample size of 85, thereby weakening the relationship because the original sample size was 56 which was then reduced to 54. The study did not explain what happened to 2 of the participants in the experiment.