I genuinely have no idea what could be causing that on the forum's end, so I have to assume the issue is specific to your iPad.
Maybe follow these instructions and clear Safari's cache?
Step 1: Launch the settings app of your iPad through the home screen.
Step 2: Scroll down the menu and select Safari.
Step 3: Scroll down to the bottom of right hand panel and tap on Advanced.
Step 4: Select website data.
Step 5: Select Remove All Website Data option at the bottom of the screen.
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This option is more flexible than the default one on Safari.