I am trying to export monthly ndvi values for 2007 for my asset 'M2007' which is a mangrove extent shapefile. I've been able to export following the same code, the monthly ndvi values for 2012, apart from one month that was missing a value (I'm not sure why either).

What can I do to acquire this data?

https://code.earthengine.google.com/3eb83ce8d46725356b871d94c663f97e

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function maskL457sr(image) { var qaMask = image.select('QA_PIXEL').bitwiseAnd(parseInt('11111', 2)).eq(0); var saturationMask = image.select('QA_RADSAT').eq(0);

var opticalBands = image.select('SR_B.').multiply(0.0000275).add(-0.2); var thermalBand = image.select('ST_B6').multiply(0.00341802).add(149.0);

return image.addBands(opticalBands, null, true) .addBands(thermalBand, null, true) .updateMask(qaMask) .updateMask(saturationMask); }

var l7 = ee.ImageCollection("LANDSAT/LE07/C02/T1_L2") .filterDate('2007-01-01', '2007-12-31') .filterBounds(roi) .map(maskL457sr)

var months = ee.List.sequence(1, 12);

var monthlyNDVIList = months.map(function (month) { var startDate = ee.Date.fromYMD(2007, month, 1); var endDate = startDate.advance(1, 'month');

var l7Monthly = l7 .filterDate(startDate, endDate) .median() .clip(roi);

var ndvi = l7Monthly.normalizedDifference(['SR_B4', 'SR_B3']);

var meanNDVI = ndvi.reduceRegion({ reducer: ee.Reducer.mean(), geometry: roi, scale: 30, maxPixels: 1e9 }).get('nd');

return ee.Feature(null, { 'Month': month, 'Mean_NDVI': meanNDVI, }); });

var monthlyNDVICollection = ee.FeatureCollection(monthlyNDVIList);

Export.table.toDrive({ collection: monthlyNDVICollection, description: 'Monthly_NDVI_2007', folder: 'GEE', fileFormat: 'CSV' });