Tempo detection problem

:open_mouth: Hi I have a tempo detection problem (in Cubase 10 Pro on brand new Merillion dedicated PC).
My track has no tempo or drums is just acoustic guitar and voice and in order to enable Cubase to detect the tempo correctly I created a reference audio track with the tempo tapping on a mic. The new track is very clear and very regular even if the song has strong tempo variations in speed.
The tempo detected in the tempo track after selecting the reference track is ok but in few places has some extra bits (3 instead of 2) in between the hits.
There is no way to get rid of them or delete them. If I try to delete them Cubase exit the tempo track and if I stretch the tempo reference points that effects my audio tracks speeding or slowing the whole song even if the tracks are not in tempo mode??
What am I missing? I cannot believe that Cubase tempo detection is so rudimental that doesn’t allow to adjust what has been detected.
Once the tempo has been detected it should allow to adjust it without affecting anything else, correct?
Thanks for your help.