Noob user, run into an error on prototyping attempt

Question

I'm making my first attempt at creating a Service and API prototype. I've been following this guide https://medium.com/madhash/prototype-your-app-with-firebase-api-7a51325de6f2

I've reached the step of "Run > Run Function > Initialize" but i'm getting an error relating to the code.gs I've pasted in from https://gist.github.com/dottedsquirrel/b248e5098fe2a9c860ed60f7db7c7e1d

The error i'm getting is "We're sorry, a server error occurred. Please wait a bit and try again. (line 49, file "Code")" When I look at the line of code it states: var ss = SpreadsheetApp.openById(sheetID);

Can anyone provide me some pointers as to how to resolve this error? Could there be a problem with the data set I created? The data sheet i'm pointing looks like this:

ID	ItemFunctionalID	ItemFunctionalID	Type	CustodianGroupID	ProcessScopeID	CountryID	StartDt	EndDt	Status
1	28948190843	Release	100199	200002	01/01/2021	Active
2	28948190843	Release	100011		01/01/2021	Active
3	28948191024	Release	100199	200002	01/01/2021	Active
4	28948191024	Release	100011		01/01/2021	Active
5	28948191031	Release	100199	200002	01/01/2021	Active

Thanks!

Answer 1

I tried to run the code by:

Run> Run Function > Initialize

And it didn't work, instead try to go to select function, select initialize and then press the triangle on the left to run the script.