The Property Ombudsman said it had received 110 complaints about these tenancy fees still being levied, while the Property Redress Scheme reported 115, according to The Times.
Letting agents are required to join one of these two redress schemes.
The National Landlords Association said that it had received significant numbers of calls to its advice line when the ban was introduced, noting that official guidance was only published two months before the ban was introduced.
It added that it was vital that in future the government allowed time for landlords, agents and tenants to understand new laws.
And David Cox, chief executive officer of ARLA Propertymark, said that it was clear the ban had already had a large impact, pushing agents to sell up and leave the sector.
He told The Times: “It was complex legislation that doesn’t fully come into effect until 2020, and therefore it’s unsurprising there is confusion, which is producing complaints.”
Others were not so sympathetic though, with housing charity Shelter suggesting that some agents and landlords are “trying to pull a fast one”.