Tether (USDT) coins were frozen for several hours on September 17 due to technical issues experienced by Omni Layer, the underlying protocol for the stablecoin, backed by US Dollar. The Omni Layer team admitted that the backend client stopped responding. As it was used by the parsing engine that feeds data to Omniexplorer and Omniwallet, the glitch caused an abrupt drop of Tether trading volume.«We have identified the issue with a backend client used by our parsing engine that appears to have locked up/become non‐responsive. We have restarted all applicable processes and are monitoring them while they verify & resync. This process should take ~ 2–3 hours to complete,» Omni Layer explained on Twitter.