a stange question for the chart

 

This question almost kill me, I found a strange thing in MT5:

 When I open MT5 or the connect recreate with MT5 server, it is happen:

1.the bars on the chart forward to current time;

2.the new bars will lost  , the chart appear like yesterday;

3.final ,all is ok.

The question is so strange, how to prevent? 

Documentation on MQL5: Date and Time / TimeCurrent
Documentation on MQL5: Date and Time / TimeCurrent
  • www.mql5.com
Date and Time / TimeCurrent - Documentation on MQL5