You have upgraded PPA to the latest 11.5 version.
Open PPA Provider Panel > Top > Infrastructure > Service Nodes > Web/Mail service node > General tab > Capacities. The capacity tab shows less sites that it actually is.
Check that PPA Provider Panel > Top > Tasks > Periodic > Scheduled Tasks > Schedule daily maintenance was finished with success.
This issue has been considered as software issue #PPA-158.
This issue will be fixed in future updates.
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