Problem reading Unique ID in STM8S208RB

Hello all,

I would like to use the Unique ID in a code written for a STM8S208RB, but it seems not to be where it is supposed... Following the datasheet (DocID14733) information the Unique ID it is supposed to be in 0x48cd. Each time I read these area I get different results :( (I have attached some screenshots). Is any instruction needed to be executed before reading the Unique ID?

Thanks for your help!