Time stamp not saved for first field group

[cocodedesigns]

I am using the CMB2 tabs on one of my CPTs, and one tab has a series of repeating field groups. Each group contains two text fields and a date/time field. In the first group, the timestamp is not saved, but in every subsequent group, it is saved. It does not matter which order the fields are placed in the group, the first group always misses the timestamp value.