Hello Aspirant,
As long as you have submitted all of the correct mark lists and accompanying documents; with your actual percentage (98%); and the only mention of your computer centre wrongfully recording a mark of 78%, I do not believe it should have any bearing on your qualification or admit card for UG entrance because the exam authority has to look at your documentation during the scrutiny process.
In fact, you should contact the appropriate examination authority or helpline promptly to call attention to the error. I would do this in writing or by official university email, attach copies of your mark sheets and indicate the mistake. At least this way, your eligibility has been clarified so when we get to the selection or counseling stage, it can't be raised there.
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