I can t. There s nothing in the contract which says you have the right to terminate.
Parties entering contracts are, in general.
Where contracts are written, the law presumes as a starting point that what s written is a true record of what they agreed of the consensus ad idem . We have to consider the terms and conditions and the schedule as what they are separate parts of one whole contract. They have to be considered together, alongside each other, in order to work out what the terms of the whole contract are. Words used have their ordinary English-language meanings. There s no express term in the contract giving you the right to terminate.