unknown connection org.nuxeo.ecm.core.storage.sql.ra.ConnectionImpl@7250e715 in org.nuxeo.ecm.core.storage.sql.ra.ManagedConnectionImpl@76952389

when I am trying to update the platform I get this error and also I have deleted one workflow form studio but it is not updating in platform and when ever I make changes in studio platform is not getting update full it shows unknown connection error at last but the changes that I made will get updated