Cant go to next challenge

i cant go to next challenge i come back at exercise i have done .i have donate 3 dollards but while now i am at the first step

If it’s a challenge that opens a new page, just clicking the “Open in new tab” button will activate the “Finish challenge” button. (You are not required to donate. It just asks you too look at the donation page.)

You can also skip challenges by going to