Excel File Locked for Editing by 'Another User': Overcoming Network Name Recognition Issue

When opening an excel file on the network, I get the message: the .xls file is locked for editing by the user "another user".
The problem is that excel gives as "another user" my network name. Even though I don't have any programs running, I blocked xls myself?
The file cannot be overwritten or deleted from the network. I can't edit and save it. How to deal with the problem?

Make sure you have write permission to the drive where the file is located. These symptoms are like the disk is read-only.

I have permissions because I created this file myself. I can use "save as" to save the file under a different name. I can't replace these files afterwards.
However, I do not have any administrative rights.

but by entering a given location you can delete the file through explorer? Can you create files but not delete anymore?

Added after 29 [seconds]:

write what operating system

On a network location I can save and delete (e.g. create another txt file and delete it), I can open a file and save it. I can't open for editing (because I can open only for reading) only this one xls because I have it locked by myself.

Added after 14 [minutes]:

Thanks for your interest, problem solved.
The "other user" is actually a different user, although the info window lists my login as the person using the file.
Some glitch I guess...

Added after 2 [minutes]:

I didn't realize that ".xls file is locked for editing by user "xx" should be read not as locked by "xx" but locked for "xx"