What is the type of sharing link? Whether the external team that can be accessed normally and the external team that cannot be accessed normally in the same domain?
First, you can do a simple troubleshooting according to below tips.
1.Try to remove the sharing link for the external team that cannot be accessed normally, then re-share again, compare the result.
2.Check whether set conditional policy in the AD of this tenant.
3.Try to share another folder with external team that cannot be accessed normally, compare the result.
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