I cannot re-enroll to a course that I failed and some other discrepancies

Dear Ladies and Gentlemen,

I failed [L1-DW] KNIME Analytics Platform for Data Wranglers do to a misunderstanding on my side (I had an issue in my dataflow which I fixed by now). Unfortunately I cannot re-enroll, after having some “reloading” issues with my browser, of which I do not know where that issue came from.

Furthermore it shows courses that I did years ago a second time, as If I made them in the last days?

Thank you very much in advance!