A certificate is labeled as not trustworthy by the REDDOXX

The public certificate is recognized by the REDDOXX and saved in the Public Certificates storage, but is not labeled as trustworthy and valid

For a public certificate to be marked as trustworthy and valid, the certification chain itself needs to be available and marked as valid.

The Root Certificate needs to be imported or the existing root certificate needs to be validated.
After doing this, the Public Certificate will be labeled as trustworthy and valid.