It is rare for a service to suspend withdrawals from a cryptocurrency wallet due to congestion, even in the case of Bitcoin, high fees were imposed or even attempts were made to delay transactions and other solutions, since the end user is the one who bears those fees and not the platform. Therefore, this suspension is related to maintenance in the withdrawal system.
Really unusual of the transaction network being on suspense but in the case regarding that it was a consequence of maintenance and services, we can always consider the inconveniences to be of the network users benefits for smooth and secured transactions.
I learnt that as much as bitcoin is being more adopted on daily basis, users are being overcrowding the network with transactions so, based on technical reviews, services to accommodate such latitude would be required to put in place.
As for the over charge of transaction fees as a result of congested networks, personally it feels bad to be experienced yet the transaction is not going smoothly.