Check out Gocardless.com 78.
They have reliable and well documented API, or you can use their console.
They take care of all the collections for a small transaction fee and make the payment to you tide account a few days after collection.
We have been using GoCardless.com 65 for years now, and recommend and integrate it for many of our clients. Remember that as you get charged by TIDE for each incoming credit payment, you may want to have payments collected on specific days e.g the 1st and 15th of the month, so you only have two credits from GoCardless per month which will cost you 40p with TIDE. You can pro-rata the initial payment to achieve this with GoCardless.com 65