I imported 10 Party, 40 ContactMech, 10 PostalAddress, and 22 TelecomNumber records from another install of OFBiz, same release (16.11.03). I added a new Party, and a new PostalAddress ContactMech record no problem. I went to add a TelecomNumber ContactMech record for the same new Party, and received a key conflict error. I hit save again and could see that the error messages were incrementing the ContactMech key through all of the imported record's Id keys. After the 41st attempt to save the record, the Telecom record finally saved. It would seem the mechanism that the TelecomNumber ContactMech type uses to detect the next ContactMech key is not reading the SEQUENCE_VALUE_ITEM table to get the next key. Log attached.