Monthly minimum ISA payment?

Hi, does anyone know if there is a monthly minimum ISA payment?

From the support article:-
“ The minimum investment to open any InvestEngine account is £100. Once you’ve put at least £100 into your InvestEngine account, you can add further one‑off amounts or set up monthly investing by standing order or direct debit.

The minimum top‑up by instant bank transfer is just £1, while there are no minimums for manual bank transfers or standing orders. There is a £50 minimum for direct debits.”