Text field with numbers and or letters

you might be able to set the field properties via the API_SetFieldProperties
https://help.quickbase.com/api-guide/index.html#setfieldproperties.html%3FTocPath%3DQuick%2520Base%2...

number formatting is:  "&numberfmt="
for no cammas: "0"

URL:

https://target_domain/db/target_dbid?a=API_SetFieldProperties&fid=7&numberfmt=0&apptoken=app_token

If the api response says "No error" then you are good to go.  I haven't tested it. But I've forced field properties on fields that normally don't give you the option before.

I'm on Essentials so no API.

Another workaround option is to change the field to a numeric field. 
Then it will give you the settings option to chose the comma usage.  change it. save it. then change the field back to text.

If you already have data in there with letters. I'd recommend duplicating the field and testing, so you don't lose your data.

(Again, I've never had to do it this way, but sometimes changing the field type will carry over old attributes)

I will try it. Thank you. 
Seems like this should be a standard setting for a text field since I'm sure many people deal with P.O. numbers like AT48094 .

I will write a support ticket. When I get a response I'll copy you.

Just as a follow up....
I created a ticket with QB support. Explained in detail. I know it wasn't my imagination because I found other with the same experience. One that gave me the.....change to numeric then back to text....which worked.
QB support said it should not be adding commas in a text field.
So, I added a new TEST text field this morning to the same table where the situation occurred. 
Lo and behold it behaved correctly. I'm writing it off to an anomaly. But as a programmer and developer for 35 years my instinct was to track down what was causing it. Glad it was resolved.

Thank you for your help.