Lookup- Way Of Searching For A Job Number Across All 31 Days

Due to the company that i work for doing alot of manuafacturing each and every day, i need some sort of look up.

For example, the currently excel sheet i use.

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As you can see i have many different Job Numbers that i use.... BUT

The problem that i am facing is, that these jobs sometimes are carried over to more than one day, [sheet bottom of screenshot] but also we might make the job one day and and then not again untill next week using the same Job Number.

What I Need
I need a way of searching for a job number across all 31 days and for it to total up the "Quantity (Qty)" of them all that we made upon that Job Number.

So lets say the Job Number 91294 was run on day 1 (shown in screenshot).
And it made 25.
But it then ran again 3 days later on the same Job Number 91294.
And it made 20.

I need it to be able to work that out the total for me across them days being 45 upon the Job Number 91294.

Things to Consider
The layout will NOT change, no extra rows or coloums will be added.