Note that Balogna and Balagna are two different places. You will not find baptisms from Corbara in the registers of Balogna.
Another place where these baptisms could be found is the Archives of Corsica (same website for both départements). But for Corbara, only registers from 1802 on are online (I do not know if earlier registers exist but are not digitized, or are lost).
Also, in 1720, Corsica was not part of France but of the Republic of Genoa, so rules for keeping records were not the same. It seems that some rural places did not have registers at all.