Replacement battery stuck at 99% during first calibration charge

I just replaced the battery in a First Gen iPhone SE with an iFixit battery and am trying to do the calibration but the charging won’t go above 99% on the first charge. It has now been on 99% for the past 4-5 hours. Is this an issue or is this just cause it is still calibrating? and I should just start discharging it to shut off?

Thanks