The error reported:
Access to apmservices-gateway-ao-apm.app.gpus1.saas.broadcom.com was denied
is a known issue with the UI in SaaS and it is already being corrected by Sustaining Engineering and SaaS Operations.
It has no impact other than having to change from AXA to DX-OI and from there to DX APM to continue working normally.
The correction is expected to be included in the next available AXA version.