Have you looked at
this page?
A quote from the FAQs
Some of our products may prompt you to activate additional codecs (MPEG2, MPEG4, Dolby Sound or AVCHD). These functions are required for the software to be able to read and write the video or audio format you are trying to use. The activations are there due to licencing purposes with the original developers of the codecs.
Normally the codec can simply be ordered by selecting the Order Online option. Here, you will be asked to login with your registered Email address and the activation code will be sent to your email.
Have you registered your product with them?
Gerry
System: Win 10 Pro (21H2), Asus X99-E WS, CPU i7-5930K -3,5 GHz, 32 GB DDR4 2666-16 RAM, NVidia GTX 1080 Ti GPU - 11 GB VRAM(Driver Studio-536.99), Samsung 850 Pro 512 GB SSD, 6 TB HD storage.