The following error appears when a reseller try to open a PA subscription in CP:
PA control panel is currently unavailable. Please try again later.
The following is shown in PBA-S debug log (/var/log/hspc/hspc.log):
The server encountered an internal error (Can't login as user %poa_login_name%) that prevented it from fulfilling this request.
Resellers do not have ability to manage PA subscriptions through CP in current PBA-S implementation. The feature will be considered and probably implemented in future PBA-S version released after 4.5. You can track it using the following ID:
PBAS-29276 - Reseller cannot manage PPA subscription through CP: "PA control panel is currently unavailable"
As a workaround for now it's suggested that resellers login to PPA panel through
RCC > Service Director > Parallels Automation Manager > Nodes > %ppa_node% > General Settings > Login to PCP