Yes, indeed. Seems like they have a problem with their wallet.
I have made a few tests on the network:
1. payment to myself using the network: https://chainz.cryptoid.info/xvp/tx.dws?9ff264fec9efeaa809927d9d99dc75256bb408a06d5f5834fa30b0c6bf6f1503.htm - worked just fine
2. payment to NovaExchange: https://chainz.cryptoid.info/xvp/tx.dws?15f73c00abef0c41ae178e76a40f06f6bba803004fea4e7be2e1a0b4262f8bed.htm - worked just fine
3. withdrawal from NovaExchange: https://chainz.cryptoid.info/xvp/tx.dws?a8192baff696eb848fcf0df49ba2d1b8ea1436b11925fb1774e493ca54ba1920.htm - worked just fine



Everything is working very well, so let's wait for the result of their maintenance. Nothing to worry about