You probably tried to upload a file that is too large. Please refer to documentation for a workaround for this limit.

1) Navigate to PHP Setting –> PHP.ini Configuration. Search for the line upload_max_filesize = 2M and post_max_size = 8M and change its value to 100M. After changing value click save.

2) Now you have changed value to 100mb and it must also reflect in phpMyAdmin