In sheet "Selection" I input a Gender (M or F) in column A, and a corresponding value in column B.

[![enter image description here](https://i.stack.imgur.com/ophj7.png)](https://i.stack.imgur.com/ophj7.png)

In sheet "Sizes", I have lists of the available sizes for each gender, like this.

[![enter image description here](https://i.stack.imgur.com/RuqSH.png)](https://i.stack.imgur.com/RuqSH.png)

In sheet "Selection", I want it to write on Column C the corresponding size (that must be always be higher than column B). If there is not an available size, it must write "Not available!"

[![enter image description here](https://i.stack.imgur.com/DC3dH.png)](https://i.stack.imgur.com/DC3dH.png)