Thanks - my Station ID is 15926. However I have solved the problem. In case anyone else has this issue. I discovered that on the Oregon display unit the rainfall total was showing 'hhh', rather than a numeric value. I cleared this setting by pressing the MEM button (as described in the handbook) and now it is recording and uploading rainfall readings correctly. I don't understand what had gone wrong, (possibly some storage or buffer was full?) but hope this post might save someone else time in future.