I'm trying to create a job in Alfresco that search documents created between a range of dates and send it automatically.
Generally speaking you should avoid making Lucene search queries. Lucene is a low-level query language that was sort-of standard in old versions of Alfresco, but since then (at least for last 4-5 years) it has switched over to becoming a legacy language only kept for backwards compatibility. At the moment, only Alfresco FTS and CMIS query languages are fully endorsed as reliable / standard query languages.
With reagards to your range query, it looks like you are missing the timezone indicator in the ISO8601 date format, as well as the milliseconds segment and (potentially) the escaping of the colon characters. You are also only using \- when escaping the dash in the date expression where it should probably be \\- (like your escaping of the colon in the Lucene field selector). With Alfresco FTS I usually simply enclose the entire ISO8601 date expression in double quotes and thus do not have to deal with escaping special characters.