I sent a return on my own

[mclachlan.dmv]

I know Im a lame but I didnt have access to a printer that wouldnt create questions from family.  Being the library’s and the employment centers are closed.

So instead of using the return info  that eBay provided, I went to the post office and sent the package on my own. Since I did not have a Q-code. 

Now I need to notify eBay and the seller of the tracking number of the return package. I can’t seem to find the FIELD where I would contact eBay to notify them of the new information on the return.

I took a picture of the Tracking # to the return & the Q-code can anyone point me in the direction of how to contact them?
Thank you for input. Have fun, stay healthy. 
Move your body! 

[labs118]

in the return case there should be a spot to upload the tracking number
This is an older screenshot but look at the return case can you click mark as shipped  as shown below & if so it should ask for tracking