Need to apply a filter via URL in CX Sales

Hello,

I need to create a filter based on a REST URL, or alternatively via SOAP in OIC. The issue is that I am trying to create it using a custom field. The field is called PersonDEO_SUUM_UltimaActualizacionPerfil_FDS_c. This is a date-type field and it is searchable in CX Sales.

Here is the URL I am using: https://ccwz-test.fa.us6.oraclecloud.com/crmRestApi/resources/11.13.18.05/contacts?q=PersonDEO_SUUM_UltimaActualizacionPerfil_FDS_c>=2025-09-22T00:00:00Z AND PersonDEO_SUUM_UltimaActualizacionPerfil_FDS_c<=2025-09-22T23:59:59Z

This approach returns data. However, the problem is that, for example, on these dates there are no records, but it still returns all records, as if it ignores the filter. I have tried various filters, and they work, but only with CX’s own date fields.