Poor service - refrain from usage of website

I bought an item from a really nice person via the bidorbuy platform. Unfortunately, bidorbuy stipulates that their courier - Internet Express - must be used for courier service. Internet Express is pathetically useless! As a result of many attempts to contact the courier from myself and the seller I still do not have my item. I now must proceed with a case of theft at the police station- I’m furious - as a customer I should not have to endure this level of stress. And my poor seller shouldn’t need to deal with this either. Bidorbuy needs to replace their courier service with a reputable honest courier. I will not stand for such poor service. And bid or buy offers no compensation or ways forward for such treatment - in 2023- this service is not acceptable- sort your business out!!!