Context: Ive created a task that creates agreements. A few fields are mandatory and some are not.

Mandatory: Supplier, Description, Year, Startdate, Enddate, type and managers.

There's functionality written in order to automaticly determine the startdate and enddate. For instance. when inserting 2023, startdate becomes 1-1-2023 and endate becomes 31-12-2023. 

There's also functionality written to determine the managers based on the first selected supplier.

Problems: 

1. Can't close my task popup if execute is clicked but the mandatory fields are not supplied.

2. Year functionality stopped working on start and enddate, now I need to select dates manually.

Gif of the behavior below.

Steps to reproduce:

1. Create bonus agreement
2. Fill in Supplier 1, no multiple suppliers (category and assistant category manager will be filled in)
3. Fill in Description
4. Click Execute (all error messages for fields that are not filled in will appear here)
5. Fill in Year
6. Click Cancel - this does not work
7. Fill in start and end date (this is problem 2)
8. Choose bonus agreement type - the Create bonus agreement window disappears

What would solve my problem?:

Being able to cancel my pop after bugging it. I want this to work as expected (meaning you can click cancel even when it bugged)

How can I achieve this?

Gif: