Elastic Search Upgrade Nest.dll 7.17.1

Question

After upgrading Nest.dll from 6.8 to 7.17.1 I'm getting the following runtime exception after executing this piece of code:

if (client.Indices.Exists(IndexName).Exists)

Exception:

  at System.Threading.SemaphoreSlim.CheckDispose()
   at System.Threading.SemaphoreSlim.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken)
   at System.Threading.SemaphoreSlim.Wait(TimeSpan timeout)
   at Elasticsearch.Net.RequestPipeline.FirstPoolUsage(SemaphoreSlim semaphore)
   at Elasticsearch.Net.Transport`1.Request[TResponse](HttpMethod method, String path, PostData data, IRequestParameters requestParameters)
   at Elasticsearch.Net.ElasticLowLevelClient.DoRequest[TResponse](HttpMethod method, String path, PostData data, IRequestParameters requestParameters)
   at Nest.ElasticClient.DoRequest[TRequest,TResponse](TRequest p, IRequestParameters parameters, Action`2 forceConfiguration)
   at Nest.NamespacedClientProxy.DoRequest[TRequest,TResponse](TRequest p, IRequestParameters parameters, Action`2 forceConfiguration)
   at Nest.Specification.IndicesApi.IndicesNamespace.Exists(IIndexExistsRequest request)
   at Nest.Specification.IndicesApi.IndicesNamespace.Exists(Indices index, Func`2 selector)

Please help me with resolving this issue.