Alarm not triggering

I`ve set up a lot of alarms of this kind without any issues, i don't know if there is a problem in cloudwatch or if I´m, missing something somehow

Basically I have a filtered metric that grabs info from a log stream, then my alarm catches when there is new incoming data to the stream and the alarm is triggered

as stated I`ve 5 other alarms of this kind running without any issue, triggering as it should be, but with this last one, it does not work

so far I've tried, changing periods, threshold, deleted and re-created the alarm, deleted the metric and re-created again and nothing works

Any advice is much appreciated :)

Thanks

 "MetricAlarms": [
        {
            "Dimensions": [], 
            "Namespace": "AnaliticoMetricsNew", 
            "DatapointsToAlarm": 1, 
            "ActionsEnabled": true, 
            "MetricName": "ErrorInGaps", 
            "EvaluationPeriods": 1, 
            "StateValue": "OK", 
            "StateUpdatedTimestamp": "2019-11-15T18:32:37.577Z", 
            "AlarmConfigurationUpdatedTimestamp": "2019-11-15T21:55:31.440Z", 
            "AlarmActions": [
                "arn:aws:sns:us-east-2:xxxxxxx:AnaliticoAWSNotification"
            ], 
            "InsufficientDataActions": [], 
            "AlarmArn": "arn:aws:cloudwatch:us-east-2:xxxxxxxx:alarm:GapsFailing", 
            "StateReasonData": "{\"version\":\"1.0\",\"queryDate\":\"2019-11-15T18:32:37.571+0000\",\"statistic\":\"Sum\",\"period\":300,\"recentDatapoints\":[],\"threshold\":1.0}", 
            "Threshold": 1.0, 
            "StateReason": "Threshold Crossed: no datapoints were received for 1 period and 1 missing datapoint was treated as [NonBreaching].", 
            "OKActions": [], 
            "AlarmDescription": "when a gap fails", 
            "Period": 900, 
            "ComparisonOperator": "GreaterThanOrEqualToThreshold", 
            "AlarmName": "GapsFailing", 
            "Statistic": "Sum", 
            "TreatMissingData": "notBreaching"
        }
    ]