react-native java.security.cert.CertPathValidatorException: Trust anchor for certification path not found – React native

My React Native mobile application suddenly cannot connect with the backend.
(only android version, iOS works without any problem).
Also I can request the API without problem by using the browser.

This just suddenly happened, when the problem start where were no changes in the server side or in the mobile application, but all android apps stop to connect to the server.

The exception in the mobile application says:
java.security.cert.CertPathValidatorException: Trust anchor for certification path not found.

I have reviewed every answer in Stack Overflow but nothing works so far.
These are the main points:

• My mobile app is made with react-native and Expo, the SSL certificated is issued by LetsEncrypt.
• The certificate from my API is correct, it works perfectly with iOS and any web browser.
• The backend is a react-js application running with an nginx 1.22.1 server.

In the mobile:

• I tried another app (api tester) for android and I get the same error trying to communicate with my API. (but again, my ssl certificate seems to be OK).
• In my mobile app, I tied to fetch data from a random open API in internet and it works without problem.
• I also tried to use fetch instead of axios but also fails to connect.
• I also look how to do an ssl certificate pinning as a temporary solution but the problem is that I’m using expo and I didn’t find the way to do it with it.

Some relevant dependencies version are:

"dependencies": {
    ...
    "axios": "^1.1.3",
    "expo": "^44.0.0",
    "expo-cli": "^5.4.3",
    "react": "17.0.1",
    "react-native": "0.64.3",
    "react-native-gesture-handler": "~2.1.0",
    ...
  },

In the server:

• I tried with a certificate issued by ZeroSSL but still have the same problem.
• I also tried add the certificate issuer to the "trusted credentials" in android, but this issuer already was in there.
• I also tried renew the certificate using certbot with the flag --preferred-chain="ISRG Root X1"

Given all this test it seems to be a server side problem, but no other device have problem with it, only android; Also I test the certificate and its OK

I also test the certificate with this website
https://www.ssllabs.com/sstest

And this was the result

SSL Test

I will be grateful for any clue you can give me.

Regards!