In such situation you can use following PowerShell script to force the delete operation:
Connect-ServiceFabricCluster -ConnectionEndpoint <your-cluster-connection-endpoint>
$nodes = Get-ServiceFabricNode
foreach($node in $nodes)
{
$replicas = Get-ServiceFabricDeployedReplica -NodeName $node.NodeName -ApplicationName "fabric:/Your-App"
foreach ($replica in $replicas)
{
Remove-ServiceFabricReplica -ForceRemove -NodeName $node.NodeName -PartitionId $replica.Partitionid -ReplicaOrInstanceId $replica.ReplicaOrInstanceId
}
}