The two codes, P0736 (https://www.yourmechanic.com/article/p0736-obd-ii-trouble-code-reverse-incorrect-gear-ratio-by-valerie-johnston) and P0730 (https://www.yourmechanic.com/article/p0730-obd-ii-trouble-code-incorrect-gear-ratio-by-ian-swan) overlap to some extent insofar as possible faults. If the transmission fluid got really low, the transmission might have overheated with several consequences: burnt fluid; mechanical damage, case/part distortion, damage to hydraulic...
Code P0730 (https://www.yourmechanic.com/article/p0730-obd-ii-trouble-code-incorrect-gear-ratio-by-ian-swan) is linked to the problem you are describing. Therefore, it's worth ruling in or out the typical causes of code P0730 which include dirty transmission fluid, low fluid, blocked filter, broken mechanical components within transmission, internal blockage...
