Hi,
Please run a database integrity check and see if that resolves your issue. You'll find it in Acymailing->Configuration->Security. Open the Advanced section and scroll down.
In case this does not resolve your issue, I kindly request that you submit a support ticket through our website at https://www.acymailing.com/support/. Our team will be able to efficiently and effectively provide you with the assistance you need.
Please note that our ticket support is exclusively available for our customers with an active Essential or Enterprise license. If your license has expired or you are using the Starter version, we kindly invite you to renew or upgrade your license prior to opening your support ticket.