APM) NA error "Configuration download failed"

Hello, 
Have a look in this article

https://techdocs.f5.com/kb/en-us/products/big-ip_apm/releasenotes/related/relnote-edge-client-7-2-5-3.html#:~:text=1697301,connection%20with%20TLS1.2

This may match known issue 1697301 in the APM Client 7.2.5.3 release notes. It states that on Windows 10, VPN connection with Edge Client/WebVPN/Machine Tunnel/Custom Dialer may fail when TLS 1.3 is used. In your topology, the client negotiates TLS 1.3 with the SSL VA, so the client-side connection is still TLS 1.3 even though the SSL VA talks to APM with TLS 1.2. As a test, force TLS 1.2 on the client-facing SSL VA profile or test from Windows 11. If TLS 1.2 fixes it, this is likely the known issue.