Cannot Download Purchased eBooks on Takealot eReader

I am trying to download my ebooks on the Takealot ereader app. I followed the instructions exactly- I have logged into my Adobe account etc. before trying to download.

It keeps saying 'this item was originally downloaded with a different user account or adobe ID'. I tried mine and my mother's (the only other possible one), and neither work. It keeps asking for a different Adobe ID.

Please help ASAP. Thanks