Analyse following RPM build log snippet. Describe contents accurately, without speculation or suggestions for resolution.            
Your analysis must be as concise as possible, while keeping relevant information intact.
Snippet: 
Problem 3: nothing provides requested (crate(base64-url/default) >= 3.0.0 with crate(base64-url/default) < 4.0.0~)

Again, the issue is that a suitable version of this crate isn't available in your RPM build environment.