How can I get my SIMPLE algorithm to work?

Hi there. I've been working on this for over a month without any success. I've simplified it as much as possible, but I feel like I'm missing some basic understanding in how the SIMPLE algorithm works (I'm just working off journal articles). Here's a version of my code for a 2x2 grid with velocity inlets and a pressure outlet, with two symmetry planes (if I've implemented that correctly). Its supposed to have Rhie-Chow interpolation but I've removed that for now until I can get solutions I'm happy with. I know my U answer is right, but my V answer is very wrong, and that's before you even look at the P solution! Please please please, any help will be greatly appreciated!

[Star Strider]

I don’t do CFD, so this is new to me. One description is The SIMPLE Algorithm for Pressure-Velocity Coupling, however I don’t know if the notation matches the notation you’re using.

It will really help if you comment your code so those reading it can understand what you’re doing. (You will be able to as well, if you put it aside for a while and then need to change it later. Don’t imagine that you’ll remember how your code works later — you won’t!)

[Mudasar Zafar]

I want to learn matalab programing for FVM please help me