Lost transactions after disconnecting and reconnecting bank account

my connection to my bank account has been showing error messages and not working as it should recently, i was advised from QB support to disconnect my bank and reconnect. upon doing so, ive now lost around 2 years worth of reviewed bank transactions. they have disappeared from from a certain date. although manually imputed cash transaction have remained, as well as some of my outgoing bank transactions. except for the most recent month which everything has disappeared. im so confused to why this has happened. 

currently support are trying to see if they can fix this, has this happened to anyone else?!? 

two years of transactions is HUGE if i have to go back manually and sort this out, its going to take hours, if not days to back track all of that information.