I’ve mentioned the solution as well, bro. But, let me rephrase it if that was confusing.
Basically, the child table does not handle the ‘Link’ type properly, hence, avoid having such a field in the child table and try to use other data types but If that breaks your requirement then you shouldn’t be using the child table in the first place.
Also, please be noted that webforms will be removed from v13. Check out the announcement from the founder: [v13] Some proposed big changes to desk, routing and Web Forms
Hope, it helps!