That's because it's a bad formula.
NaHCO does not exist. Can you please make sure that you have copied everything correctly? An equation balancer I use (when I change NaHCO to NaHCO3, since I'm pretty sure that's what you meant):
5 CH3O2 + 4.758098676965E-16 NaHCO3 = 4 H2O + 2.2204460492503E-16 Na2O + C5H7O6
Warning: some compounds do not play role in the reaction and have 0 coeficients
And with NaHCO just because:
5 CH3O2 + -1.3322676295502E-15 NaHCO = 4 H2O + -6.6613381477509E-16 Na2O + C5H7O6
Warning: some compounds do not play role in the reaction and have 0 coeficients