Go to COMPONENTS->MijoShop
Then go to SALES->USERS->Customer Groups
Click EDIT next to the Default user group.
Set “Display Company No.:” to NO
Set “Display Tax ID.:” to NO
If it is still showing after this, you need to download this free OpenCart extension:
Unzip the file and upload the companytaxfieldremover.xml file through FTP to
/components/com_mijoshop/opencart/vqmod/xml/