Hi experts,
We're using Apex 20.2 and we've upgraded ORDS from 19.2.0.r1991647 to 20.4.1.013.1644.
We've had this error and was temporarily solved by bouncing Tomcat:

ProcedureForbiddenException [statusCode=404, logLevel=INFO, errorCode=ORDS-22001: The procedure named f could not be accessed or found Cause: The procedure may not be declared, or the user executing this request may not have been granted execute privilege on the procedure, or a function specified by security.requestValidationFunction configuration property has prevented access Action: Check the spelling of the procedure, check that the execute privilege has been granted to the caller and check the configured security.requestValidationFunction function]
at oracle.dbtools.apex.ModApex.validateRequest(ModApex.java:427)
at oracle.dbtools.apex.ModApex.doGet(ModApex.java:152)
at oracle.dbtools.apex.ModApex.service(ModApex.java:119)
at oracle.dbtools.http.entrypoint.Dispatcher.dispatch(Dispatcher.java:126)
at oracle.dbtools.http.entrypoint.EntryPoint$FilteredServlet.service(EntryPoint.java:170)
at oracle.dbtools.http.filters.FilterChainImpl.doFilter(FilterChainImpl.java:73)
at oracle.dbtools.http.forwarding.QueryFilteringRewrite.doFilter(QueryFilteringRewrite.java:90)
at oracle.dbtools.http.filters.HttpFilter.doFilter(HttpFilter.java:47)
at oracle.dbtools.http.filters.FilterChainImpl.doFilter(FilterChainImpl.java:64)
at oracle.dbtools.http.forwarding.ForwardingFilter.doFilter(ForwardingFilter.java:68)
at oracle.dbtools.http.filters.HttpFilter.doFilter(HttpFilter.java:47)
at oracle.dbtools.http.filters.FilterChainImpl.doFilter(FilterChainImpl.java:64)
...
Any ideas? Thanks!