There have been many reports about suppliers being out of stock. Below is a message received recently from my supplier:
"Ordering items on back order.
Does not necessarily mean the item is out of stock.
The current availability is very good at the moment. (March 2020)
The ordering process for us has changed slightly, The pharmacies in Thailand do not hold stock anymore; this is due to the cost and affects most pharmacies.
Therefore the pharmacies require money upfront, only then will they place the order with their supplier.
The process is a little slower and may or may not affect delivery times".