My navigation tab just disappeared?

My entire navigation tab just disappeared, I’ve done everything possible to comprehend on how to troubleshoot this problem even by changing my entire theme and still nothing. I asked for assistance through customer service and the robot kept repeating the same non solutions to my problem. So this is my last resort before deleting this entire platform because I just don’t have the time to understand something that can be so simple to resolve but yet very complicated if you’re not a web developer or understanding coding.

Please send the store url and examples of the issue.

Thanks