In reply to rkg_:
The first thing any data (read or write data) used together with the RAL has to be of type
uvm_reg_data_t
Dou you see the write data are arriving in the DUT?
I cannot give you a good advice bedause I do not know which access type the corresponding register has. And your protocol implementation to assign the read data from the data bus might be incorrect.
What is your error message? Which kind of data do you see when reading?