On Dec 26th, 2017, I created a DGB wallet using "Digibyte Go."  I sent some DGB to the wallet.  Now, 3 years later, I'm trying to access them and the wallet balance says zero.  However, it shows the transaction from 2017 as "received."  When I look up the address on the block explorer, the coins are there.  Why is this wallet not working properly?  Also, it seems I did not save a back up phrase because 3 years ago, I didn't know. THX!