btw, as you use a portable version anyways:
you could try out the portable version of notepad++ 7.6.3 from >>> here <<< extract it to a new folder, and update dspellcheck.
on 7.6.3 run `plugins > plugins admin > updates" and update dspellcheck to 1.4.9
(note: “plugins admin” is only available on portable notepad++ since version 7.6.2)
if dspellcheck is the cause of your issue, you can also update to dspellcheck 1.4.10 manually from >>> here <<< and retry.
if technical informations are of interest to you, you can re-read following dspellcheck issues, based on the research of @guy038 :
https://github.com/Predelnik/DSpellCheck/issues/139
https://github.com/Predelnik/DSpellCheck/issues/151