@sedat_kendirci1 please note that the Smartlogger & inverter's password accept only Numbers and Letters.
So if you have changed it to Admin@12345 (as an example), in fact the password is only Admin12345 (it doesn't accept special characters like @#$!*& etc)
If still doesn't work, send and email to eu_inverter_support@huawei.com with Smartlogger's SN and they will help you.