The P0700 code tells you that the TCM (transmission control module) asked the PCM to illuminated the CEL. It's an indication that there is a DTC stored in the TCM. The code can be cleared from the PCM (by disconnecting the battery for 15 minutes) but if the transmission issue is not resolved, it will just return later.
What work was done to the transmission and was the CEL on before the work was done?
Maybe some auto tranny experts can chime in too?