Number safe and acces on specfice time

Basically my problem is that I want to store a randomly generated number and use it later.

This is the full explanation

I want a randomly generated number for a machine 1,2 ... n
(Depends on which machine is chosen.)
Creations that are requested on a specific day and time.

On 12/3/2021 I want to use machine 2 from 8:30 to 12:30 and I order this on 9/3/2021 at 15h this creates a code that must be requested on 12/3/2021 at 8:30

I hope you will explain this because I don't think it is real and the reservation data would normally be taken from a website but could also be retrieved from an excel file, these are 12/3/2021 8:30 and 12:30 data

I am going to thank you in advance because I am not really digging out thank you very much

Looks like a repetition from this other post ? If not what is the difference ?

Yes it is kinda but this goes a bit further in depth in to 1 spefice thing i thought it was beter to make a new one so less confusion i thought it was better this tell me if i was wrong and it would have been beter to reply on that other post i will stop this one and post on the other one if so sorry for the inconvince

Please continue on your original post.