Step 1: Download the path, as shown in the screenshot below, After downloading the patch download the build version which is compatible with your php version, so that you can replace the add-on module.
Step 2: After extracting the built got to the path as shown in the screenshot (\whmcs\modules\addons\ -> In local ) and (/modules/addons/ -> In server )
Note : Please keep the backup of the existing folder in you local
Step 3: Now from local go to the patch folder that you have extracted
Step 4: Now navigate to the path shown below in the screenshot on both local and server, then upload the selected files as shown below to the given path.
Step 5: Now navigate to the above given path on both sides as shown below, Here we will override the file , Once this is done Upload the 2 files on your server on the below shown path and after successfully completing all the steps your module will be compatible with whmcs 8.8.X
