Why can't I exchange Ethereum (ETH) to Bitcoin (BTC)?

I'm curious to understand why I seem to be encountering difficulties in exchanging my Ethereum (ETH) holdings for Bitcoin (BTC). As a seasoned investor in the cryptocurrency market, I've always found the process of swapping tokens relatively straightforward. However, this time, despite trying multiple platforms and exchanges, I'm unable to complete the transaction. Could it be due to liquidity issues on the selected platforms? Or perhaps there are some technical issues with the blockchains involved? I'd appreciate any insights or explanations that could help me navigate this challenge.