Discord bots only ever get the permissions you explicitly granted when generating the invite link, plus whatever is further limited by their role's position in your server's role list. Two separate checks, both need to pass.
Check 1: the invite link's permissions
If a command needs to do something (manage messages, kick a member, manage roles), that specific permission needs to have been included when you generated the invite link in the Discord Developer Portal's OAuth2 URL Generator. If it wasn't, re-generate the invite link with the right permissions checked and re-invite the bot.
Check 2: role position
Discord's permission system is hierarchical: a bot (via its own role) can never manage a role or move a member with a role positioned above its own role in Server Settings → Roles. If a moderation command silently fails against a specific member, this is the first thing to check, drag the bot's role higher in that list.