Replacing the monitor is the only option.  Just about no one repairs monitors, even as paid work -- and even if you can find the panel needed to replace the screen, monitors just are not designed to be repaired. Dell is, as a US company, prohibited by law from supporting anything distributed in Russia or its allies. You should not, however discard the monitor in the trash -- take it to a recycling center if you mean to dispose of it.  
Two days ago, my AW2721D monitor showed a vertical blue line. I bought this monitor a few years ago (around 2020, I don't remember exactly, sorry). But its made on December 2020, so the warranty should be active at least until December 2023. The product page of this monitor says it should expire on March 26, 2024. I called Dell International Support because I live in Slovenia and found out they can't do a thing about it. Because the warranty on this expensive monitor is suspended (because of the sanctions), call your Dell reseller. I called them, and the Russian Dell distributor says it can't help (since the warranty is suspended (by Dell?)) either. The most frustrating part is that I can't do anything. This monitor was bought long before sanctions and conflict. I even moved out from Russia to Slovenia and I can't do anything about it. Dell can't help, the distributor can't help, and the monitor can't be fixed. And what should I do now? Throw it into the trash or what?
AW2721D, Russian Dell distributor, warranty suspended