[GNC] Rounding issues with Stock

[NS]

First, let me tell you I am a recent user of GNUCash, and by no means I am
a bookkeeper or know a lot about accounting.
I am using the tool to keep control of some stock I own.

Here is my issue.
I have a DRIP on the stock. My broker says the reinvested price of each
share was $26.4884, and they bought 4 shares for a total value of $105.9536.

Now, I cannot enter four decimals in the buy (I do not know if it is a
setting), even though the price handles them.
When I recorded the transaction in GNUCash y entered 4 shares and a buy of
$105.95 and a price of $26.4875 was calculated.

If I enter 4 shares and the price of $26.4884, it recalculates it to
$26.4875.

How do I solve this? I want to keep track of the correct numbers.

Thanks for your help.