Sorry I didn't put this through livesql but it is not applicable for this question.

I have created and OCI Free Tier ATP DB and I have installed Oracle Apex.

I have created an application and a public page in the application with a form based on a table that has a blob column.

If the page is not public I can successfully upload a document and open it.

If I change the page to public and try to upload a document again when I click submit is says 'it is not possible to upload a file on a public page on this instance'.

I have checked this document but I don't see anything that says I should not be able to do this.
https://docs.oracle.com/en/cloud/paas/atp-cloud/atpug/apex-restrictions.html#GUID-E13D5044-B9DD-4168-8A12-C99532940DA9

So my next step was to check the APEX Instance ALLOW_PUBLIC_FILE_UPLOAD parameter using an admin account via SQL Dev and via my Apex Admin login and the sql commands screen (this latter option was never going to work but I tried it anyway)

This is the output from running using my ATP DB admin account via SQL Dev

BEGIN
APEX_INSTANCE_ADMIN.SET_PARAMETER('ALLOW_PUBLIC_FILE_UPLOAD', 'Y');
END;

Error report -
ORA-20987: APEX - Instance parameter not found - Contact your application administrator.
Details about this incident are available via debug id "125044".
ORA-06512: at "APEX_200100.WWV_FLOW_ERROR", line 1132
ORA-06512: at "APEX_200100.WWV_FLOW_ERROR", line 1499
ORA-06512: at "APEX_200100.WWV_FLOW_INSTANCE_ADMIN", line 87
ORA-06512: at "APEX_200100.WWV_FLOW_INSTANCE_ADMIN", line 190
ORA-06512: at line 2

So all I am basically asking is it possible to upload a file publicly on the OCI Free Tier via a public apex page or is it just a missing parameter?

I can understand the reasons if it is not possible to do this but I am trying to understand how I can check what is and isn't possible as the documentation that I have found doesn't appear to say it isn't possible.

Any information is greatly appreciated.