Hi,
That's really strange. Your template has an override for the pagination to generate its own HTML, and has CSS specific to that HTML.
However, the result is like you can see, as if it was made like that deliberately.
As Philippe said, the best would be to check with your template provider as that situation is not normal. The template provider might have a solution it can implement to fix the issue, like improving a bit its CSS.
Now, a simple solution should be to rename the file templates/YOUR_TEMPLATE/html/pagination.php via FTP.
It will disable the pagination override of your template and it should then display the same as protostar.