My FIT file that I combined won't upload to Garmin Connect

I did a workout in my coach plan and it registered as a normal run (despite having the correct thresholds and measurements ..I did it a day early I think was the problem)
SO I did the workout today for 2 secs, merged the two files and when I go to import the merged file it says "We don't support the file type you tried to import." then I cleaned the file using the a logger to fix the timestamp and I got "One of your files was not accepted by the system. Please contact Support for assistance.".

What can I do to get my run imported onto my planned activities?