According to ABRF delta mass site (https://www.abrf.org/delta-mass), there are a few candidates.
First a couple of questions:
1. Is +70 with a proton?
2. Are you operating in positive or negative ion mode detection?
If this is an associated ion, by switching the polaritiy of the detector, you can see if it disappears. Eg., :Peptide solutions kept in glass vials tend to show Na and K adducts during positive ion mode detection and they disappear when you switch to negative ion mode on MALDI-TOF MS.
Also the peak +70 shows the same pattern of Na and K adducts. It looks I have 2 compounds. I suppose that the additional peak comes from impurities of the starting materials or glassware.