Sumif problems

[MissingInAction]

Hi everyone
I have created a proforma invoicing system in Excel for our landfill site. I have a sumif formula that calculates the total weight of each type of waste (General, mixed waste & large rubble) and then it gets multiplied by the tariff. This is on the "Region 1" sheet. Companies are grouped in different regions. Region 1's companies gets billed individually (Region 1 sheet), while the companies of Region 2, 3 and 4 gets billed as a group, respectively (Region 2, 3 and 4 sheets).
This works perfectly for 234 companies listed on the "Database" sheet, however company 235 and 236 gives me a #REF! error. I do not understand why.
Furthermore, Region 3 and Region 4's sheets are identical when it comes to the formulas, but Region 3 is also giving me the #REF! error while Region 4 is working fine. Region 3's sheet is giving me the issue because company 236 has a #REF! error. I checked my source data and the database many times and found no errors with the names/details of the companies.

The "cover letter" sheet is basically a summary of the total cost for every company regardless of what region it falls in. The purpose of this sheet is to sign off the costs of all the companies as a whole so that it is not needed to sign each bill individually. You will see the error company 235 and 236 gives there as well.

I have added the file to make it easier to troubleshoot. I also removed company information, for obvious reasons.
Here is the file:

Dropbox

www.dropbox.com

 

[Fluff]

Try filtering the calculation sheet col C for Customer 235

 

[RoryA]

Look at rows 3283 onwards on the Calculations sheet.

 

[MissingInAction]

Ah something so simple. Thank you. That data comes from the previous version of the file that I modified, but somehow did not see the issue there.