Thanks for reaching out,
Regarding the data ingestion in general, nothing has changed at our end, you can test this by making a post request to
industrial.api.ubidots.com and our data ingestion endpoint
/api/v1.6/devices/<device_label>/ just like indicated in our documentation here using any HTTP client of your choice for instance Postman. Notice that I get a 201 response code which indicated the data was stored.
Having this in mind I suggest you check first the connectivity of your device to the internet or any changes on your network that may prevent the connection, also try to connect to a different server and see if that also fails, if all that is good, then try sending any random data to Ubidots perhaps by using the examples we have with regards to the use of our library and check the results and response codes.
Also in order to help if the problem persists we would need more details like the version of your NodeMCU and the Serial monitor output when running one of our code examples.