Why is my Vauxhall Astra's transmission slipping?

I've noticed that my Vauxhall Astra's transmission has been slipping, especially when shifting gears. It's also making strange noises. What could be causing this issue and what can I do to fix it?

It's most likely due to low transmission fluid. Check your fluid levels and top up if necessary. If this doesn't solve the issue, it could be a sign of a more serious problem and you should take it to a mechanic.

Another possibility is that the transmission filter needs to be changed. If it's clogged, it could be causing the slipping and strange noises.

If you've recently had any repairs done on your transmission, it's possible that something was not reassembled correctly. You should take it back to the mechanic to have it checked.