Handshake SSL error. SSL routines tls_process_server_certificate

Hi team,
Since today we have been getting the following error after submiting a form.

HTTPSConnectionPool(host=‘gp2-test-release.suremptec.com.ar’, port=443): Max retries exceeded with url: /api/v2/mobile/?alternate=geoplatform:capa_para_kobo_imagen (Caused by SSLError(SSLError(“bad handshake: Error([(‘SSL routines’, ‘tls_process_server_certificate’, ‘certificate verify failed’)])”)))

We have already update our certificate.
"let’s encrypt” certificate expired yesterday.

Could you support us ?
thanks in advance.

Welcome to the community, @pablopace! Are you on a self-hosted server?

No. We are using Kobo’s server “Researchers, Aid Workers & Everyone Else”

Besides that, we are using LetsEncrypt https://letsencrypt.org/ as our Certificate Authority. They updated their CA certificate on 9/30/2021