Failing to get Sailing permit before leaving the US

Hello! 

I have stayed in the US under L1B visa in 2023. My visa was valid till August 2024, however, I had to leave the US on December 13, 2023. I have not visited the US since then, but I got a couple of payroll through a US entity and some interest through US banks. 

I am now preparing to file for 2024 as a non-resident alien , and I suddenly learned that I was supposed to get a sailing permit before leaving the US. 

I have never heard of it before and had no idea I needed to do it.

I am not leaving in the US for more than a year now and did not visit is (I am a non-resident allien now). All my taxes up to 2023 are paid and I am planning to file as a non-resident allien for the income I had through the US source in 2024. I have not done anything specifica before leaving the country (as I did not know I needed to) and my visa expired in August 2024. 

Do I need to get the sailing permit now? If so, how can I get it (since I am not living in the US anymore and not planning to go there soon).

If I cannot get it, what implications on my taxes (or other) can I have?

Also, what forms and where (online) can I file for my US source income as being a non-resident allient? 

Thank you so much for your advice!