To renew your SLC there are some things you need to do - mostly it is have recently logged some sailing time (10 days in past 2 years or 5 days in past year) and retake the online SLC exam.
When you go to your International License tab you will then see anything that is in red that needs to be completed. You can click on the [?] next to each item to learn more.
Here below, the user needs to take the online SLC exam again as it expired in 2018 (this is 2021 now)
To take the online SLC exam again, just go to your curriculum page.
When you get to your online SLC exam you will see everything as passed - that's because you passed it previously. But you need to do the SLC exam again to make sure you stay current with knowledge. Get started by simply clicking on Module 1 and take the test then more to Module 2 etc. Remember that the SLC exam is not a course - it is just an exam so you should be able to fly through it pretty quick.
(we might write a bit of code that automatically puts it back in your incomplete courses every 2 years - but for now, it is probably in your completed courses area under your curriculum)