Hello,
As mentioned earlier, this issue is related to Customizations and there are no errors in the Default Files provided. You can check the HTMl Validation errors in your Codes here: https://validator.w3.org/nu/?doc=https%3A%2F%2Fwww.wowsers.nl%2F, which also gives the Line Number of the Error. Due to the HTML Validation errors, the #wrapper is not closed properly which makes the #footer push to the bottom.
Unfortunately, you will need to fix this yourself as we currently do not provide Customization related Support according to the Item Support Policy: https://themeforest.net/page/item_support_policy .
Most possibly, this is the error in your code:
Simply remove the `` from the above code. it is highly recommended to properly format and align your codes to prevent any confusions in the future.
Let us know if we can help you with anything else or if you find any further issues.