Is there anything wrong with my block

when I use preview it keeps crashing or showing a white background without anything

Ending amount >= Target amount is not a good condition. Your loop will not run until ending amount = Target amount and then run for ever. You killed your app!
I think it should be ending amount =< target amount.
Your label will also keep changing and will most likely show the last calculated values.
Why not add those results to list to show all?

Ive had the same problem if you can simplify it and delete some blocks it maybe it wont crash because it has less information to proses.

Hopefully this helps, Will

Can you send me a link to your app to help you further?

I found out the problem dy is because of the decimal places, i think it overloaded the system

When I take away the decimal places it work fine

Nice good fix

When someone offers you help and it works, always acknowledge. It does not cost anything to say thank you. The block ‘repeat until’ will not work if you didn’t change the operation >= to =< as I earlier advised.
It’s obviously the problem you had, not decimal.