Why does CopyRates only give a limited amount of data?

There are 2 options for getting data. 
Open
the strategy tester, select the tool and run it in the specified period for TF = 1 minute. We get all the candles in the OnTick function.
The second
option is written in the CopyRates code for a given tool with TF = 1 minute. But in the end, we only get data for the last 5 months, although
in fact there are much more of them on the server. 

I also checked this with the function 

Print("The very first date by symbol-period at the moment=", (datetime)SeriesInfoInteger(Symbol(),Period(),SERIES_FIRSTDATE));For some reason,
it displays the date from August, but if I check in the strategy tester, I can get the data much earlier with TF = 1 minute

How can I fix this problem? You must use CopyRates to get any data that is available on the server.