Can we get approval flow logs more deital than "Run Diagnostics Tests" result?

Summary:

Can we get approval flow logs more deital than "Run Diagnostics Tests" result?

Content (please ensure you mask any confidential information):

My user told me that he had to submit approval button in notification but the notification appeared again in work list next morining.

The approval history showed no approval result and I executed "Run Diagnostics Tests". Its result also showed no apprval result.

I think it might happened misoperation or something. But user insisted he clicked the button.

So I want to know if we can get more detail approval flow logs more than "Run Diagnostics Tests" results.