I suppose that it is BIP39 seed, what is exactly the error that you get when trying to enter the seed on your wallet?
Try this:
Download electrum from
Here.
Then open it, enter the name of the wallet, press next. Then standard wallet -> I already have a seed -> Press options -> Select bip39 seed.
Then enter your seed on the field and press okay. Then your wallet should load all of your balances, and you should be able to spend your bitcoins.
If you dont want to download electrum, you can just use the
Bip39 tool for all kind of needed information like private keys and such (just remember to save the page for offline mode).
I hope this reply this reply helps you