A method performed by a wireless device (120) for handling a first transport block received from a transmitting device (101) is provided herein. The first transport block comprises a first set of code blocks. At least a first subset of code blocks has been unsuccessfully decoded by the wireless device (120). The wireless device (120) and the transmitting device (101) operate in a wireless communications network (100). The wireless device (120) determines (802), based on a first number of unsuccessfully decoded code blocks, a second number of code blocks to be allocated in a first memory (1111) of the wireless device (120), to store the unsuccessfully decoded code blocks. The wireless device (120) also allocates (803) the determined second number of code blocks. The wireless device (120) then initiates (805) storage of the unsuccessfully decoded code blocks in the first set, in the allocated determined second number of code blocks.