An IFA who was part of failed network Honister Capital says some providers refused to take his calls when the business went into administration in July, leaving him unable to keep clients informed about their investments.
Andrew Elson, now a financial planner at Beaufort Asset Management, said the difference in how providers treated him shocked him.
"There were some providers who bent over backwards to help - and some who wouldn't even speak to us. Mortgage providers were among the worst."
Elson praised Aviva and Skandia as "fantastic" during the troubled times with Honister, where he was an appointed representative. But he said Axa Elevate was among the worst.
"Elevate wouldn't take our calls. It just told us to speak to the administrator. Scottish Widows took a while to decide whether it would re-open its systems to us. Some providers just turned off their electronic systems. It was like you didn't exist."
When the Honister Capital network collapsed, about 900 advisers lost their Financial Services Authority (FSA) authorisation.
A spokesperson for Axa Elevate said it would have been in breach of data protection rules if it had allowed unauthorised advisers access to client information.
"We can only give access to client systems to authorised advisers, or if we have a letter of authorisation from the client," he said.
But Elson said providers should take a more client-centric approach in future.
"Going forward providers need to know their place in the circle. At the moment it's not how it should be, not like we're both sitting on the same side helping the client."
Elson wants to see providers share their resources with advisers more.
"The client is the key to all of this, they have got to be looked after properly and not like a commodity. Providers have a wealth of knowledge and technical support - that should be shared with advisers for the benefit of the client.
"Instead providers are writing to clients telling them about adviser charging when really that's something I should be doing."
View from the front row
Project Libra unveiled
Including SJP and investment trusts
Spent two years at Sanlam
Will also assess FCA's actions