Google App Engine TextSearch Update/Delete 15,000 per minute quota limit exception

[Sri via StackOverflow]

We are getting following Quota limit exception when we are updating textsearch document,

com.google.apphosting.api.ApiProxy$OverQuotaException: The API call search.IndexDocument() required more quota than is available. at org.jboss.resteasy.core.SynchronousDispatcher.handleApplicationException(SynchronousDispatcher.java:365) at org.jboss.resteasy.core.SynchronousDispatcher.handleException(SynchronousDispatcher.java:233) at org.jboss.resteasy.core.SynchronousDispatcher.handleInvokerException(SynchronousDispatcher.java:209)

and code is

public SearchService searchService = SearchServiceFactory.getSearchService();

public Index index = searchService.getIndex(IndexSpec.newBuilder().setName("contacts"));

Document.Builder docs = Document.newBuilder();

docs.addField(Field.newBuilder().setName("first_name_start").setText(first_name.substring(0, 1)));

index.put(docs);

any suggestion towards resolving it?

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