Arduino UNO + Tamiya twin gearbox + 298 H bridge. Please help.

Regarding the power supply for the motors so far I have tried 5 volts so it`s a bit more than the 3.3 volts advised for this motors. When I supply 5 volts directly to the motors they run well. However, when I supply the 5 volts through the H Bridge they don't move at all.

Thanks.