#RIF! inside formulas after every refreshing Power Query

Good morning everyone.
I will try to be exhaustive in explaining this Excel drawback.
I have created an Excel model that through PowerQuery appends and modifies about 150 .txt files contained in a folder.

I don't think the details of the files are imported but they are made of 4 columns with thousands of rows with
state + country + zipcode + number of inhabitants

After appending the files I generate a table with as many rows as there are files and 3 columns of
state + country + zipcode attributes.

Once I have made my changes in PowerQuery I load the generated table in the Excel sheet and to the right of it I build a model with calculated columns that will be part of the same table element.
Many columns are VLOOKUP or SUMIF on the zipcode column--> the key.
Up to here everything is ok.
The problem is that often when I update the model and add txt files or replace files in the folder, the columns on the right of the table generated by the query ((therefore from the 4th column onwards)) generate an error. The error is dictated by the fact that the internal reference of the VLOOKUP or SUMIF formulas is deleted by displaying #REF! .. even if the column to which they refer named ZIPCODE always exists without any modification.
I can't solve this problem .. do you have any ideas?

Hi,
it's really difficult for me to upload the entire model..
I've other model where I use in a stable way formulas that link into tables column give by Power Query..

The strange thing is that the formulas give me error are not the same between refreshes,...

Hi,
thanks for all your suggestion but I've been able to solve the issue.
The key point is that I initially build the table with all formulas without the connection with Power Query, once I built the formulas and test if model worked I've subsitute the first 3 colum with the output query of power Query having the same data structure.
Now I've just tried to rebuild the entire model from scratch starting with the Power Query Table.. after that I tried to test tha same situation in wich a refresh of the datas leads to a #RIF! into formulas and... It'S works!
The model built with Power Query Table since beginning continue to works without problem unlike the previous version even if at data level are the same!

without example I cannot agree or not agree with this method but if it works that's fine. Good Luck