I get an internal error when moving an article at Pangasinan Wikipedia

Steps to Reproduce:

Example:

1. Go to https://pag.wikipedia.org/wiki/Europe
2. Move to target page https://pag.wikipedia.org/wiki/Europa
3. Check box for "Leave a redirect behind" then click "Move page"
4. Europa exist as a redirect so check box for "Yes, delete the page" then click "Move page" again

Result:
Internal error
[XEJIdwpAMFEAADncrjkAAAAF] 2019-01-18 21:43:19: Fatal exception of type "MWException"