Sorry about the trouble with Lightroom Mobile. We're here to help.
Which version of the application are you using? How are you trying to upload? What is the file format of these files? Which version of Lightroom Mobile and Android are you using? Where are these photos located, internal drive or external memory?
Please log on to Lightroom web (https://lightroom.adobe.com) and check if photos are getting synced with the cloud version or not. Try re-login into Lightroom.
We're here to help, just need some more info.