Why is Coinbase not allowing me to buy?

I'm curious to know, why exactly is Coinbase preventing me from making a purchase? Is there a specific issue with my account that needs to be resolved? Or is it a broader issue affecting multiple users? I've checked my account balance and my payment methods are all up-to-date and valid, so I'm at a loss for why I'm unable to proceed with a transaction. Could you please provide some insight into what might be causing this issue and how I can go about resolving it?