detu: this might be part of the verb defero which looks suitable in the context (cf. 127-9) but the traces at the left of the next line are not easy to reconcile with an appropriate verbal ending.
We take this to be an interlinear correction to line 3b. If ].om is the end of a word cf. saluom, 225.6.
ad is very uncertain.
inscrib/en]dam looks a likely restoration, perhaps erased. If the context is legal it might be connected with cognitionem, whether the bungled attempt before it or the word after it, which has clearly not been erased. inscriptio in its legal sense, however, means "accusation" and the verb inscribere is not used with cognitio as a direct object (see TLL VII.1 1848 and perhaps note Digest 184.108.40.206, si libellos inscriptionum deposuerit). We cannot elucidate the supralinear addition at the end of line 3a; the last three (or four) letters are very obscure indeed and may themselves have been erased.
misi has not been erased (the horizontal line through mi is the grain of the wood). What follows has certainly been erased. It might begin with ad.