VGTM and MTOF has been discontinued for quite a while now. Beyond has stopped selling them, so if you did not purchase it before they got discontinued, you cannot get their Legacy content anymore. The only way for you to access them at this point is to join a campaign with content sharing on where at least one person in the campaign has bought them.
If you do not mind having the current official versions, then you can buy MP:MOTM instead. MP:MOTM has most of the content from VGTM and MTOF updated to more modern standards.
I really want Kenku, Goliaths, Tabaxies and other races! I cannot access Volo's guide to monsters on Marketplace, any ideas?
That book has been discontinued and is no longer available for retail. You can purchase the updated versions of those species in Mordenkeinen’s Monsters of the Multiverse: (https://www.dndbeyond.com/marketplace/sourcebooks/mordenkainen-presents-monsters-of-the-multiverse).
Creating Epic Boons on DDB
DDB Buyers' Guide
Hardcovers, DDB & You
Content Troubleshooting
VGTM and MTOF has been discontinued for quite a while now. Beyond has stopped selling them, so if you did not purchase it before they got discontinued, you cannot get their Legacy content anymore. The only way for you to access them at this point is to join a campaign with content sharing on where at least one person in the campaign has bought them.
If you do not mind having the current official versions, then you can buy MP:MOTM instead. MP:MOTM has most of the content from VGTM and MTOF updated to more modern standards.
Check Licenses and Resync Entitlements: < https://www.dndbeyond.com/account/licenses >
Running the Game by Matt Colville; Introduction: < https://www.youtube.com/watch?v=e-YZvLUXcR8 >
D&D with High School Students by Bill Allen; Season 1 Episode 1: < https://www.youtube.com/watch?v=52NJTUDokyk&t >