Yes I have tried both voltages. You mean the link to the place I purchased them? Came from Amazon, here’s the link. Amazon.com: HiLetgo 2pcs DHT22/AM2302 Digital Temperature And Humidity Sensor Module Temperature Humidity Monitor Sensor Replace SHT11 SHT15 for Arduino Electronic Practice DIY : Appliances
Today I loaded and tried running the seeed with Visual Studio Code PlatformeIDE. It gave the same results including the failure to upload code after two or three uploads. I wonder if the code is being uploaded not over the old code but appended to the old code, hence the ram is being filled up then further uploads are blocked. Just a wild guess of course.