All of my efforts were to no avail.Everything I did to help was of no avail. Nothing worked.
of no avail
Of or having very little or no benefit, efficacy, or effect. We did our best to keep Sarah from finding out about her dad, but it was of no avail.I protested of no avail to keep Jeff in the company.
of little/no aˈvail
(formal) of little or no use: Your ability to argue is of little avail if you get your facts wrong.