When heat is applied to a block of ice at -10°C, its temperature will indeed begin to rise. However, once it reaches 0°C, the ice will undergo a phase change from a solid to a liquid (melting). During this phase change, the temperature of the ice will remain constant at 0°C until all the ice has melted.
Once all the ice has melted, the resulting water at 0°C will then begin to absorb more heat, causing its temperature to rise further.
