Script to update records in another table

So I for this scenario I have 2 tables. One is called DID the other is called E911.  I have data in both tables.   In both tables there is a piece of information that may be the same.  In DID I have a field DID Number (text field) and a field E911 (Yes/No field).  In E911 I have Associated Number (text field), Date of Last Update, Location name, and Location(which is linked from a table called Addresses). 

Since both tables have data I really don't want to have to empty one and manually populate or copy/paste.  I would like to accomplish two things.  First to have a script run on update that checks the DID table field E911 (Yes/No) and if yes to force entering data into the E911 table (location etc...).  

Below is the script as written thus far, though I am running into issues.  In particular in the update script on the DID table it fails on the field name (which I have verified is correct).

if this.E911 then
    let existingRecord := (select E911 where 'Associated Number' = this.'DID Number');

    if count(existingRecord) = 0 then
        let newRecord := (create E911);
        newRecord.('Associated Number' := this.'DID Number');
        newRecord.('Company' := this.Company); // Adjust field name if necessary
        newRecord.('Location' := this.Location); // Adjust field name if necessary
    else
        for record in existingRecord do
            record.('Company' := this.Company); // Adjust field name if necessary
            record.('Location' := this.Location); // Adjust field name if necessary
        end
    end
else
    let existingRecord := (select E911 where 'Associated Number' = this.'DID Number');
    if count(existingRecord) > 0 then
        for record in existingRecord do
            delete record;
        end
    end
end

Once I get this part working I will work on the second part which is a script to compare the two tables and update accordingly.  Ideally I would only want the "Numbers" stored in the DID table and referenced in the E911 table only if the E911 (Yes/No) is set to Yes.

My guess is I am making this a lot harder than it needs to be.  I have done some database work in the past but it is not my day to day job and its been a few years.  Any and all help/tips/points in the right direction are welcomed.

Thanks,