Comment 1 for bug 2065798

This issue here is you have selected both TLS 1.2 and TLS 1.3 for the pool, but you have provided ciphers that are valid for TLS 1.3 only. To allow TLS 1.2, there must be at least one TLS 1.2 compatible cipher included in the list.

If you add a valid TLS 1.2 cipher to the list, the member will be created properly.

For example, the "Intermediate" compatibility cipher list for TLS 1.2 and 1.3 is:

Cipher suites (TLS 1.3): TLS_AES_128_GCM_SHA256:TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256
Cipher suites (TLS 1.2): ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:DHE-RSA-CHACHA20-POLY1305

If you only want to use "TLS_AES_128_GCM_SHA256:TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256" as the only valid ciphers, you must only enable TLS 1.3.

This website can be a helpful reference for understanding valid ciphers for each protocol version:
https://wiki.mozilla.org/Security/Server_Side_TLS#Recommended_configurations